[arm] Use arm_active_target for most FP feature tests

[arm] Use arm_active_target for most FP feature tests

Now that the isa feature bits are all available in arm_active_target
we can use that for most of the feature tests that are needed.

	* arm.h (TARGET_VFPD32): Use arm_active_target.
	(TARGET_VFP3): Likewise.
	(TARGET_VFP5): Likewise.
	(TARGET_VFP_SINGLE): Likewise.
	(TARGET_VFP_DOUBLE): Likewise.
	(TARGET_NEON_FP16): Likewise.
	(TARGET_FP16): Likewise.
	(TARGET_FMA): Likewise.
	(TARGET_FPU_ARMV8): Likewise.
	(TARGET_CRYPTO): Likewise.
	(TARGET_NEON): Likewise.
	(TARGET_FPU_FEATURES): Delete.
	* arm.c (arm_option_check_internal): Check for iwmmxt conflict with
	Neon using arm_active_target.

From-SVN: r243712