RISC-V: Added Zfhmin and Zhinxmin.

RISC-V: Added Zfhmin and Zhinxmin.

This commit adds Zfhmin and Zhinxmin extensions (subsets of Zfh and
Zhinx extensions, respectively).  In the process supporting Zfhmin and
Zhinxmin extension, this commit also changes how instructions are
categorized considering Zfhmin, Zhinx and Zhinxmin extensions.

Detailed changes,

* From INSN_CLASS_ZFH to INSN_CLASS_ZFHMIN:

flh, fsh, fmv.x.h and fmv.h.x.

* From INSN_CLASS_ZFH to INSN_CLASS_ZFH_OR_ZHINX:

fmv.h.

* From INSN_CLASS_ZFH_OR_ZHINX to INSN_CLASS_ZFH_OR_ZHINX:

fneg.h, fabs.h, fsgnj.h, fsgnjn.h, fsgnjx.h,
fadd.h, fsub.h, fmul.h, fdiv.h, fsqrt.h, fmin.h, fmax.h,
fmadd.h, fnmadd.h, fmsub.h, fnmsub.h,
fcvt.w.h, fcvt.wu.h, fcvt.h.w, fcvt.h.wu,
fcvt.l.h, fcvt.lu.h, fcvt.h.l, fcvt.h.lu,
feq.h, flt.h, fle.h, fgt.h, fge.h,
fclass.h.

* From INSN_CLASS_ZFH_OR_ZHINX to INSN_CLASS_ZFHMIN_OR_ZHINXMIN:

fcvt.s.h and fcvt.h.s.

* From INSN_CLASS_D_AND_ZFH_INX to INSN_CLASS_ZFHMIN_AND_D:

fcvt.d.h and fcvt.h.d.

* From INSN_CLASS_Q_AND_ZFH_INX to INSN_CLASS_ZFHMIN_AND_Q:

fcvt.q.h and fcvt.h.q.

bfd/ChangeLog:

	* elfxx-riscv.c (riscv_implicit_subsets): Change implicit
	subsets.  Zfh->Zicsr is not needed and Zfh->F is replaced with
	Zfh->Zfhmin and Zfhmin->F.  Zhinx->Zicsr is not needed and
	Zhinx->Zfinx is replaced with Zhinx->Zhinxmin and
	Zhinxmin->Zfinx.
	(riscv_supported_std_z_ext): Added zfhmin and zhinxmin.
	(riscv_multi_subset_supports):  Rewrite handling for new
	instruction classes.
	(riscv_multi_subset_supports_ext): Updated.
	(riscv_parse_check_conflicts): Change error message to include
	zfh and zfhmin extensions.

gas/ChangeLog:

	* testsuite/gas/riscv/zfhmin-d-insn-class-fail.s: New complex
	error handling test.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-1.d: Likewise.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-1.l: Likewise.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-2.d: Likewise.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-2.l: Likewise.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-3.d: Likewise.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-3.l: Likewise.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-4.d: Likewise.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-4.l: Likewise.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-5.d: Likewise.
	* testsuite/gas/riscv/zfhmin-d-insn-class-fail-5.l: Likewise.
	* testsuite/gas/riscv/zhinx.d: Renamed from fp-zhinx-insns.d
	and refactored.
	* testsuite/gas/riscv/zhinx.s: Likewise.

include/ChangeLog:

	* opcode/riscv.h (enum riscv_insn_class): Removed INSN_CLASS_ZFH,
	INSN_CLASS_D_AND_ZFH_INX and INSN_CLASS_Q_AND_ZFH_INX.  Added
	INSN_CLASS_ZFHMIN, INSN_CLASS_ZFHMIN_OR_ZHINXMIN,
	INSN_CLASS_ZFHMIN_AND_D and INSN_CLASS_ZFHMIN_AND_Q.

opcodes/ChangeLog:

	* riscv-opc.c (riscv_opcodes): Change instruction classes for
	Zfh and Zfhmin instructions.  Fix `fcvt.h.lu' instruction
	(two operand variant) mask.