Merging r228565:

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r228565 | majnemer | 2015-02-08 22:31:31 -0800 (Sun, 08 Feb 2015) | 3 lines

MC: Calculate intra-section symbol differences correctly for COFF

This fixes PR22060.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_36@228667 91177308-0d34-0410-b5e6-96231b3b80d8