AVX-512: Fixed a bug in OR/XOR operations for 512-bit FP values on KNL.

KNL does not have VXORPS, VORPS for 512-bit values.
I use integer VPXOR, VPOR that actually do the same.

X86ISD::FXOR/FOR are generated as a result of FSUB combining.

Differential Revision: http://reviews.llvm.org/D12753

llvm-svn: 247523