Merging r259894:

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r259894 | thomas.stellard | 2016-02-05 09:42:38 -0800 (Fri, 05 Feb 2016) | 8 lines

AMDGPU/SI: Correctly initialize SIInsertWaits pass

Reviewers: arsenm

Subscribers: arsenm, llvm-commits

Differential Revision: http://reviews.llvm.org/D16724

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llvm-svn: 271594