Merging r315611:

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r315611 | abataev | 2017-10-12 13:03:39 -0700 (Thu, 12 Oct 2017) | 5 lines

[OPENMP] Fix PR34927: Emit initializer for reduction array with declare
reduction.

If the reduction is an array or an array section and reduction operation
is declare reduction without initializer, it may lead to crash.
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llvm-svn: 318120