[AVX-512] Fix register class in one of the gather/scatter memory operands so that all 32 bit registers can be allowed.
[AVX-512] Fix register class in one of the gather/scatter memory operands so that all 32 bit registers can be allowed.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@292087 91177308-0d34-0410-b5e6-96231b3b80d8

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