Merging r201096:

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r201096 | thomas.stellard | 2014-02-10 08:58:27 -0800 (Mon, 10 Feb 2014) | 6 lines

R600/SI: Only use S_WQM_B64 in pixel shaders

This doesn't change any functionality, since we only have two shader
types (compute and pixel) that use local memory.  We're just changing
the logic to match the documentation.

llvm-svn: 204647