Merging r261723:

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r261723 | mohit.bhakkad | 2016-02-24 13:44:41 +0530 (Wed, 24 Feb 2016) | 7 lines

[MSan] fix process_vm_readv test: Exit silently if syscall is not implemeted

Reviewers: eugenis

Subscribers: jaydeep, sagar, llvm-commits

Differential Revision: http://reviews.llvm.org/D17560
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llvm-svn: 270398