Merging r293021:

Merging r293021:
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r293021 | chapuni | 2017-01-24 21:26:23 -0800 (Tue, 24 Jan 2017) | 4 lines

Ignore llvm/test/tools/llvm-symbolizer/coff-exports.test on mingw.

FIXME: Demangler could behave along not host but target.
For example, assume host=mingw, target=msc.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_40@293575 91177308-0d34-0410-b5e6-96231b3b80d8