[AArch64, 6/6] Reimplement vpadd intrinsics & extend rtl patterns to all modes

[AArch64, 6/6] Reimplement vpadd intrinsics & extend rtl patterns to all modes

	* config/aarch64/aarch64-builtins.def (faddp): New builtins for modes in
	VDQF.
	* config/aarch64/aarch64-simd.md (aarch64_faddp<mode>): New.
	(arch64_addpv4sf): Delete.
	(reduc_plus_scal_v4sf): Use "gen_aarch64_faddpv4sf" instead of
	"gen_aarch64_addpv4sf".
	* config/aarch64/arm_neon.h (vpadd_f32): Remove inline assembly.  Use
	builtin.
	(vpadds_f32): Likewise.
	(vpaddq_f32): Likewise.
	(vpaddq_f64): Likewise.

From-SVN: r237205