Merging r200288:

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r200288 | hfinkel | 2014-01-28 00:32:58 -0500 (Tue, 28 Jan 2014) | 5 lines

Handle spilling the PPC GPRC_NOR0 register class

GPRC_NOR0 is not a subclass of GPRC (because it also contains the ZERO pseudo
register). As a result, we also need to check for it in the spilling code.

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llvm-svn: 205821