Revert "AVX512: Implemented encoding and intrinsics for vextracti64x4...

Revert "AVX512: Implemented encoding and intrinsics for   vextracti64x4 ,vextracti64x2, vextracti32x8, vextracti32x4, vextractf64x4, vextractf64x2, vextractf32x8, vextractf32x4 Added tests for intrinsics and encoding."

This reverts commit r247149, as it was breaking numerous buildbots of varied architectures.

llvm-svn: 247177