[AVX512] Add VLX 128/256-bit SET0 operations that encode to 128/256-bit EVEX encoded VPXORD so all 32 registers can be used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268884 91177308-0d34-0410-b5e6-96231b3b80d8
14 files changed