Merging r369749:

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r369749 | stulova | 2019-08-23 13:43:49 +0200 (Fri, 23 Aug 2019) | 5 lines

[Docs][OpenCL] Several corrections to C++ for OpenCL

Differential Revision:https://reviews.llvm.org/D64418


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llvm-svn: 370031