Revert r335562 and 335563 "[X86] Redefine avx512 packed fpclass intrinsics to...

Revert r335562 and 335563 "[X86] Redefine avx512 packed fpclass intrinsics to return a vXi1 mask and implement the mask input argument using an 'and' IR instruction."

These were supposed to have been squashed to a single commit.

llvm-svn: 335566