Correct disassembly of dot product instructions.

Correct disassembly of dot product instructions.

Dot products deviate from the normal disassembly rules for lane indexed
instruction. Their canonical representation is in the form of:

v0.2s, v0.8b, v0.4b[0] instead of v0.2s, v0.8b, v0.b[0] to try to denote
that these instructions select 4x 1 byte elements instead of a single 1 byte
element.

Previously we were disassembling them following the normal rules, this patch
corrects the disassembly.

gas/

	PR gas/22559
	* config/tc-aarch64.c (vectype_to_qualifier): Support AARCH64_OPND_QLF_S_4B.
	* gas/testsuite/gas/aarch64/dotproduct.d: Update disassembly.

include/

	PR gas/22559
	* aarch64.h (aarch64_opnd_qualifier): Add AARCH64_OPND_QLF_S_4B.

opcodes/

	PR gas/22559
	* aarch64-asm.c (aarch64_ins_reglane): Change AARCH64_OPND_QLF_S_B to
	AARCH64_OPND_QLF_S_4B
	* aarch64-dis.c (aarch64_ext_reglane): Change AARCH64_OPND_QLF_S_B to
	AARCH64_OPND_QLF_S_4B
	* aarch64-opc.c (aarch64_opnd_qualifiers): Add 4b variant.
	* aarch64-tbl.h (QL_V2DOT): Change S_B to S_4B.

Change-Id: Ie80d878ceaeaca281f85583e77e4e367e2a909ea