aarch64: gas: Allow movprfx with fmmla and bfscale [PR gas/33562]

aarch64: gas: Allow movprfx with fmmla and bfscale [PR gas/33562]

These instructions were previously incorrectly marked as not accepting
movprfx.  Fix this and add tests.

	PR gas/33562

opcodes:
	* aarch64-tbl.h: Update widening fmmmla and bfscale instructions.
gas:
	* testsuite/gas/aarch64/f8f16mm_sve2-bad.l: Update test with movprfx.
	* testsuite/gas/aarch64/f8f16mm_sve2.d: Ditto.
	* testsuite/gas/aarch64/f8f16mm_sve2.s: Ditto.
	* testsuite/gas/aarch64/f8f32mm_sve2-bad.l: Ditto.
	* testsuite/gas/aarch64/f8f32mm_sve2.d: Ditto.
	* testsuite/gas/aarch64/f8f32mm_sve2.s: Ditto.
	* testsuite/gas/aarch64/sve-f16f32mm-bad.l: Ditto.
	* testsuite/gas/aarch64/sve-f16f32mm.d: Ditto.
	* testsuite/gas/aarch64/sve-f16f32mm.s: Ditto.
	* testsuite/gas/aarch64/sve-bfscale-sve2.s: Ditto.
	* testsuite/gas/aarch64/sve-bfscale-sve2.d: Ditto.

Approved-By: Alice Carlotti <alice.carlotti@arm.com>