decompressor: only take erroneous data on first try

Ticket: 6959

We want to accept partial decompressed data with error, but only
if it is our first try, as we also want to try different
decompression algorithms if the first one does not match.

This led to use tolerating deflate which decompressed cleartext.

htp/htp_decompressors.c

@@ -317,7 +317,7 @@ htp_status_t htp_gzip_decompressor_decompress(htp_decompressor_t *drec1, htp_tx_
             return HTP_ERROR;
         }
         if (GZIP_BUF_SIZE > drec->stream.avail_out) {
-            if (rc == Z_DATA_ERROR) {
+            if (rc == Z_DATA_ERROR && drec->restart == 0) {
                 // There is data even if there is an error
                 // So use this data and log a warning
                 htp_log(d->tx->connp, HTP_LOG_MARK, HTP_LOG_WARNING, 0, "GZip decompressor: inflate failed with %d", rc);