Thumb1 register to register MOV instruction is predicable.

Thumb1 register to register MOV instruction is predicable.

Fix a FIXME and allow predication (in Thumb2) for the T1 register to
register MOV instructions. This allows some better codegen with
if-conversion (as seen in the test updates), plus it lays the groundwork
for pseudo-izing the tMOVCC instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134197 91177308-0d34-0410-b5e6-96231b3b80d8