Merging r295635:

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r295635 | brad | 2017-02-19 22:18:15 -0500 (Sun, 19 Feb 2017) | 5 lines

Enable support for __float128 in Clang on OpenBSD/X86

/usr/local/include/c++/4.9.4/type_traits:279:39: error: __float128 is not
supported on this target
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llvm-svn: 301084