ARM: Make sure the instruction alias for PLI uses the right subtarget features.

PLI requires both the Thumb2 and the ARMv7 feature.

Related to <rdar://problem/14403733>.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186620 91177308-0d34-0410-b5e6-96231b3b80d8