MIPS/GAS: Split Loongson MMI Instructions from loongson2f/3a

MIPS/GAS: Split Loongson MMI Instructions from loongson2f/3a

The MMI instruction set has been implemented in many Loongson
processors.  There is a lot of software optimized for MMI.  This patch
splits MMI from loongson2f/3a, and adds GAS and disassembler options for
MMI instructions.

2018-07-20  Chenghua Xu  <paul.hua.gm@gmail.com>
            Maciej W. Rozycki  <macro@mips.com>

bfd/
	* elfxx-mips.c (print_mips_ases): Add MMI extension.

binutils/
	* readelf.c (print_mips_ases): Add MMI extension.

gas/
	* NEWS: Mention MultiMedia extensions Instructions (MMI)
	support.
	* config/tc-mips.c (options): Add OPTION_LOONGSON_MMI and
	OPTION_NO_LOONGSON_MMI.
	(md_longopts): Likewise.
	(mips_ases): Define availability for MMI.
	(mips_convert_ase_flags): Map ASE_LOONGSON_MMI to
	AFL_ASE_LOONGSON_MMI.
	(mips_cpu_info_table): Add ASE_LOONGSON_MMI for loongson2f/3a.
	(md_show_usage): Add help for -mloongson-mmi and
	-mno-loongson-mmi.
	* doc/as.texi: Document -mloongson-mmi, -mno-loongson-mmi.
	* doc/c-mips.texi: Document -mloongson-mmi, -mno-loongson-mmi,
	.set loongson-mmi and .set noloongson-mmi.
	* testsuite/gas/mips/loongson-2f.d: Move mmi test to ...
	* testsuite/gas/mips/loongson-2f-mmi.d: Here.  Add ISA/ASE
	flag verification.
	* testsuite/gas/mips/loongson-2f.s: Move mmi test to ...
	* testsuite/gas/mips/loongson-2f-mmi.s: Here.
	* testsuite/gas/mips/loongson-3a.d: Move mmi test to ...
	* testsuite/gas/mips/loongson-3a-mmi.d: Here.  Add ISA/ASE
	flag verification.
	* testsuite/gas/mips/loongson-3a.s: Move mmi test to ...
	* testsuite/gas/mips/loongson-3a-mmi.s: Here.
	* testsuite/gas/mips/mips.exp: Run loongson-2f-mmi and
	loongson-3a-mmi tests.

include/
	* elf/mips.h (AFL_ASE_MMI): New macro.
	(AFL_ASE_MASK): Update to include AFL_ASE_LOONGSON_MMI.
	* opcode/mips.h (ASE_LOONGSON_MMI): New macro.

opcodes/
	* mips-dis.c (mips_arch_choices): Add MMI to loongson2f and
	loongson3a descriptors.
	(parse_mips_ase_option): Handle -M loongson-mmi option.
	(print_mips_disassembler_options): Document -M loongson-mmi.
	* mips-opc.c (LMMI): New macro.
	(mips_opcodes): Replace IL2F|IL3A marking with LMMI for MMI
	instructions.