AArch64: Use CMP;CCMP sequences for and/or/setcc trees.

Previously CCMP/FCCMP instructions were only used by the
AArch64ConditionalCompares pass for control flow. This patch uses them
for SELECT like instructions as well by matching patterns in ISelLowering.

PR20927, rdar://18326194

Differential Revision: http://reviews.llvm.org/D8232

llvm-svn: 238793