Merging r300267:

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r300267 | tejohnson | 2017-04-13 17:51:49 -0400 (Thu, 13 Apr 2017) | 11 lines

[Support] Fix ErrorOr assertion when /proc/cpuinfo doesn't exist.

The ErrorOr should not be dereferenced on the error path.

Patch by Jacob Young

Reviewers: tejohnson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32032
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llvm-svn: 305264