Merging r278086:

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r278086 | matze | 2016-08-08 18:47:26 -0700 (Mon, 08 Aug 2016) | 6 lines

X86InstrInfo: Update liveness in classifyLea()

We need to update liveness information when we create COPYs in
classifyLea().

This fixes http://llvm.org/28301
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llvm-svn: 278128