Emit SIMD moves as mov

Emit SIMD moves as mov

SIMD moves are currently emitted as ORR.  Change this to use the MOV
pseudo instruction just like integer moves (the ARM-ARM states MOV is the
preferred disassembly), improving readability of -S output.

    gcc/
	* config/aarch64/aarch64.md (movti_aarch64):
	Emit mov rather than orr.
	(movtf_aarch64): Likewise.
	* config/aarch64/aarch64-simd.md (aarch64_simd_mov):
	Emit mov rather than orr.

From-SVN: r249444