Second pass at addressing PR15351 by explicitly checking for AVX support when getting the host processor information.  It emits a .byte sequence on GNUC compilers to work around lack of xgetbv support with older assemblers, and resolves a comment typo found in the previous patch.
Second pass at addressing PR15351 by explicitly checking for AVX support
when getting the host processor information.  It emits a .byte sequence on GNUC compilers to work around lack of xgetbv support with older assemblers, and resolves a comment typo found in the previous patch.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@178636 91177308-0d34-0410-b5e6-96231b3b80d8

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