[ARM] Implement TARGET_FIXED_CONDITION_CODE_REGS

[ARM] Implement TARGET_FIXED_CONDITION_CODE_REGS

This patch implements TARGET_FIXED_CONDITION_CODE_REGS on ARM.

We have two main cases to consider: in Thumb1 code there are no
condition code registers, so we simply return false.  For other
cases we set the the first pointer to CC_REGNUM and the second to
VFPCC_REGNUM iff generating hard-float code.

Running the CSiBE benchmark I see a couple of cases (both in the same
file) where this feature kicks in, so it's not a major change.

	* config/arm/arm.c (arm_fixed_condition_code_regs): New function.
	(TARGET_FIXED_CONDITION_CODE_REGS): Redefine.

From-SVN: r250005