Merging r276648:

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r276648 | delena | 2016-07-25 09:51:00 -0700 (Mon, 25 Jul 2016) | 6 lines

AVX-512: Fixed [US]INT_TO_FP selection for i1 vectors.
It failed with assertion before this patch.

Differential Revision: https://reviews.llvm.org/D22735


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llvm-svn: 277508