[Patch AArch64] Fix register constraints for lane intrinsics.

[Patch AArch64] Fix register constraints for lane intrinsics.

gcc/
	* config/aarch64/aarch64-simd.md
	(aarch64_sqdml<SBINQOPS:as>l_n<mode>_internal): Use
	<vwx> iterator to ensure correct register choice.
	(aarch64_sqdml<SBINQOPS:as>l2_n<mode>_internal): Likewise.
	(aarch64_sqdmull_n<mode>): Likewise.
	(aarch64_sqdmull2_n<mode>_internal): Likewise.
	* config/aarch64/arm_neon.h
	(vml<as><q>_lane<q>_<su>16): Use 'x' constraint for element vector.
	(vml<as><q>_n_<su>16): Likewise.
	(vml<as>l_high_lane<q>_<su>16): Likewise.
	(vml<as>l_high_n_<su>16): Likewise.
	(vml<as>l_lane<q>_<su>16): Likewise.
	(vml<as>l_n_<su>16): Likewise.
	(vmul<q>_lane<q>_<su>16): Likewise.
	(vmul<q>_n_<su>16): Likewise.
	(vmull_lane<q>_<su>16): Likewise.
	(vmull_n_<su>16): Likewise.
	(vmull_high_lane<q>_<su>16): Likewise.
	(vmull_high_n_<su>16): Likewise.
	(vqrdmulh<q>_n_s16): Likewise.

From-SVN: r202322