Merging r237164:

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r237164 | thomas.stellard | 2015-05-12 14:59:17 -0400 (Tue, 12 May 2015) | 10 lines

R600/SI: Fix bug in VGPR spilling

AMDGPU::SI_SPILL_V96_RESTORE was missing from a switch statement, which
caused the srsrc and soffset register to not be set correctly.

This commit replaces the switch statement with a SITargetInfo query
to make sure all spill instructions are covered.

Differential Revision: http://reviews.llvm.org/D9582

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llvm-svn: 240283