aarch64: Add support for unpacked SVE MLA and MAD

aarch64: Add support for unpacked SVE MLA and MAD

This patch extends the MLA/MAD patterns to support unpacked
integer vectors.  The type suffix could be either the element
size or the container size, but using the element size should
be more efficient.

gcc/
	* config/aarch64/aarch64-sve.md (fma<mode>4): Extend from SVE_FULL_I
	to SVE_I.
	(@aarch64_pred_fma<mode>, cond_fma<mode>, *cond_fma<mode>_2)
	(*cond_fma<mode>_4, *cond_fma<mode>_any): Likewise.

gcc/testsuite/
	* gcc.target/aarch64/sve/mla_2.c: New test.
	* g++.target/aarch64/sve/cond_mla_1.C: Likewise.
	* g++.target/aarch64/sve/cond_mla_2.C: Likewise.
	* g++.target/aarch64/sve/cond_mla_3.C: Likewise.
	* g++.target/aarch64/sve/cond_mla_4.C: Likewise.
	* g++.target/aarch64/sve/cond_mla_5.C: Likewise.