disas/riscv: Add amocas.[w,d,q] instructions

disas/riscv: Add amocas.[w,d,q] instructions

Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20231207153842.32401-3-rbradford@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>