x86: consolidate VAES tests

There's little point in having Intel syntax disassembler tests when the
purpose of a test is assembler functionality: Drop all
*avx512*_vaes-wig1-intel.

For *avx512*_vaes-wig1 share source with *avx512*_vaes. This in
particular makes sure that the 32-bit VL test actually tests any EVEX
encodings in the first place.

Finally put in place similar tests for -mvexwig=1.