RISC-V : Support bitmanip-0.93 ZBA/ZBB/ZBC instructions

RISC-V : Support bitmanip-0.93 ZBA/ZBB/ZBC instructions

bfd/
	* elfxx-riscv.c (riscv_std_z_ext_strtab): Add zba, zbb and zbc.

gas/
	* config/tc-riscv.c (ext_version_table): Add b, zba, zbb and zbc.
	(riscv_multi_subset_supports): Add INSN_CLASS_ZB*.
	* testsuite/gas/riscv/b-ext-64.s: Bitmanip test case.
	* testsuite/gas/riscv/b-ext-64.d: Likewise.
	* testsuite/gas/riscv/b-ext.s: Likewise.
	* testsuite/gas/riscv/b-ext.d: Likewise.

include/
	* opcode/riscv-opc.h: Support zba, zbb and zbc extensions.
	* opcode/riscv.h (riscv_insn_class): Add INSN_CLASS_ZB*.

opcodes/
	* riscv-opc.c (riscv_opcodes): Add zba, zbb and zbc instructions.