Merging r340181:

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r340181 | abataev | 2018-08-20 18:00:22 +0200 (Mon, 20 Aug 2018) | 7 lines

[OPENMP][BLOCKS]Fix PR38923: reference to a global variable is captured
by a block.

Added checks for capturing of the variable in the block when trying to
emit correct address for the variable with the reference type. This
extra check allows correctly identify the variables that are not
captured in the block context.
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git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_70@340352 91177308-0d34-0410-b5e6-96231b3b80d8