Don't use enums for values read directly from the bitstream

The enums don't cover all possible values read from the bitstream.

This fixes undefined behaviour sanitizer errors.

Fixes: 27647/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_LIBFDK_AAC_fuzzer-5654559200116736
Fixes: 28193/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_LIBFDK_AAC_fuzzer-4901213455515648

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg

libMpegTPDec/src/tpdec_asc.cpp

@@ -1549,8 +1549,7 @@ static TRANSPORTDEC_ERROR extElementConfig(CSUsacExtElementConfig *extElement,
                                            const AUDIO_OBJECT_TYPE aot) {
   TRANSPORTDEC_ERROR ErrorStatus = TRANSPORTDEC_OK;
 
-  USAC_EXT_ELEMENT_TYPE usacExtElementType =
-      (USAC_EXT_ELEMENT_TYPE)escapedValue(hBs, 4, 8, 16);
+  int usacExtElementType = escapedValue(hBs, 4, 8, 16);
 
   /* recurve extension elements which are invalid for USAC */
   if (aot == AOT_USAC) {
@@ -1567,7 +1566,7 @@ static TRANSPORTDEC_ERROR extElementConfig(CSUsacExtElementConfig *extElement,
     }
   }
 
-  extElement->usacExtElementType = usacExtElementType;
+  extElement->usacExtElementType = (USAC_EXT_ELEMENT_TYPE)usacExtElementType;
   int usacExtElementConfigLength = escapedValue(hBs, 4, 8, 16);
   extElement->usacExtElementConfigLength = (USHORT)usacExtElementConfigLength;
   INT bsAnchor;
@@ -1631,14 +1630,14 @@ static TRANSPORTDEC_ERROR configExtension(CSUsacConfig *usc,
   TRANSPORTDEC_ERROR ErrorStatus = TRANSPORTDEC_OK;
 
   int numConfigExtensions;
-  CONFIG_EXT_ID usacConfigExtType;
+  int usacConfigExtType;
   int usacConfigExtLength;
 
   numConfigExtensions = (int)escapedValue(hBs, 2, 4, 8) + 1;
   for (int confExtIdx = 0; confExtIdx < numConfigExtensions; confExtIdx++) {
     INT nbits;
     int loudnessInfoSetConfigExtensionPosition = FDKgetValidBits(hBs);
-    usacConfigExtType = (CONFIG_EXT_ID)escapedValue(hBs, 4, 8, 16);
+    usacConfigExtType = escapedValue(hBs, 4, 8, 16);
     usacConfigExtLength = (int)escapedValue(hBs, 4, 8, 16);
 
     /* Start bit position of config extension */