openssl 1.x: add empty layout & factorize tests of CMake variables

[SpaceIm]

It's required for #12938 & #13458, and basically any recipe depending on openssl recipe and relying on AutotoolsDeps (see conan-io/conan#12106)

---

• I've read the guidelines for contributing.
• I've followed the PEP8 style guides for Python code in the recipes.
• I've used the latest Conan client version.
• I've tried at least one configuration locally with the conan-center hook activated.

[ghost]

I detected other pull requests that are modifying openssl/1.x.x recipe:

• openssl: updated url for old 1.x versions #13435
• openssl: Enable valid block of options for openssl >= 1.1.0 #11725
• openssl: Make debug build renaming optional #10939

This message is automatically generated by https://github.com/ericLemanissier/conan-center-conflicting-prs so don't hesitate to report issues/improvements there.

[prince-chrismc]

Service is still down, so please be gentle... it will automatically start jobs :)

[conan-center-bot]

All green in build 2 (f667f59943c4b1fd56ea15f1bfe20c25fe7b5c8b):

• openssl/1.1.1p@:
  All packages built successfully! (All logs)

  🔸 Informative: This recipe is not ready for Conan v2

  _{We have started the migration process to Conan v2 and exporting recipes successfully will be required in the future.
  This is just an informative note to gain awareness about the process, no need to take any action. The plan is to enforce smaller steps that are easier to fix and, eventually, this conan export step will work.
  See the recipe migration guide to know more about the changes required.}

  ERROR: Error loading conanfile at '/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py': Unable to load conanfile in /home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py", line 6, in <module>
      from conans import AutoToolsBuildEnvironment, tools
  ImportError: cannot import name 'AutoToolsBuildEnvironment' from 'conans' (/opt/pyenv/versions/3.7.13/lib/python3.7/site-packages/conans/__init__.py)
  

• openssl/1.1.1o@:
  All packages built successfully! (All logs)

  🔸 Informative: This recipe is not ready for Conan v2

  _{We have started the migration process to Conan v2 and exporting recipes successfully will be required in the future.
  This is just an informative note to gain awareness about the process, no need to take any action. The plan is to enforce smaller steps that are easier to fix and, eventually, this conan export step will work.
  See the recipe migration guide to know more about the changes required.}

  ERROR: Error loading conanfile at '/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py': Unable to load conanfile in /home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py", line 6, in <module>
      from conans import AutoToolsBuildEnvironment, tools
  ImportError: cannot import name 'AutoToolsBuildEnvironment' from 'conans' (/opt/pyenv/versions/3.7.13/lib/python3.7/site-packages/conans/__init__.py)
  

• openssl/1.1.1q@:
  All packages built successfully! (All logs)

  🔸 Informative: This recipe is not ready for Conan v2

  _{We have started the migration process to Conan v2 and exporting recipes successfully will be required in the future.
  This is just an informative note to gain awareness about the process, no need to take any action. The plan is to enforce smaller steps that are easier to fix and, eventually, this conan export step will work.
  See the recipe migration guide to know more about the changes required.}

  ERROR: Error loading conanfile at '/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py': Unable to load conanfile in /home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py", line 6, in <module>
      from conans import AutoToolsBuildEnvironment, tools
  ImportError: cannot import name 'AutoToolsBuildEnvironment' from 'conans' (/opt/pyenv/versions/3.7.13/lib/python3.7/site-packages/conans/__init__.py)
  

• openssl/1.1.0l@:
  All packages built successfully! (All logs)

  🔸 Informative: This recipe is not ready for Conan v2

  _{We have started the migration process to Conan v2 and exporting recipes successfully will be required in the future.
  This is just an informative note to gain awareness about the process, no need to take any action. The plan is to enforce smaller steps that are easier to fix and, eventually, this conan export step will work.
  See the recipe migration guide to know more about the changes required.}

  ERROR: Error loading conanfile at '/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py': Unable to load conanfile in /home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py", line 6, in <module>
      from conans import AutoToolsBuildEnvironment, tools
  ImportError: cannot import name 'AutoToolsBuildEnvironment' from 'conans' (/opt/pyenv/versions/3.7.13/lib/python3.7/site-packages/conans/__init__.py)
  

• openssl/1.0.2u@:
  All packages built successfully! (All logs)

  🔸 Informative: This recipe is not ready for Conan v2

  _{We have started the migration process to Conan v2 and exporting recipes successfully will be required in the future.
  This is just an informative note to gain awareness about the process, no need to take any action. The plan is to enforce smaller steps that are easier to fix and, eventually, this conan export step will work.
  See the recipe migration guide to know more about the changes required.}

  ERROR: Error loading conanfile at '/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py': Unable to load conanfile in /home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py
    File "<frozen importlib._bootstrap_external>", line 728, in exec_module
    File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
    File "/home/conan/w/prod_cci_PR-13459/recipes/openssl/1.x.x/conanfile.py", line 6, in <module>
      from conans import AutoToolsBuildEnvironment, tools
  ImportError: cannot import name 'AutoToolsBuildEnvironment' from 'conans' (/opt/pyenv/versions/3.7.13/lib/python3.7/site-packages/conans/__init__.py)