Merging r243660:

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r243660 | Matthew.Arsenault | 2015-07-30 13:03:08 -0400 (Thu, 30 Jul 2015) | 9 lines

AMDGPU: Fix unreachable when emitting binary debug info

Copy implementation of applyFixup from AArch64 with AArch64 bits
ripped out.

Tests will be included with a later commit. Several other
problems must be fixed before binary debug info emission
will work.

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llvm-svn: 253229