Merging r276119:

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r276119 | yaxunl | 2016-07-20 07:38:06 -0700 (Wed, 20 Jul 2016) | 3 lines

AMDGPU: Fix bug causing crash due to invalid opencl version metadata.

Differential Revision: https://reviews.llvm.org/D22526
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llvm-svn: 277079