RISC-V: Clarify the imply rule of c

This also fix the imply result for .option rvc.

Imply zcf when c and f and rv32
Imply zcd when c and d
Imply zca when c

Changed INSN_CLASS_C to INSN_CLASS_ZCA
Changed INSN_CLASS_F_AND_C to INSN_CLASS_ZCF
Changed INSN_CLASS_D_AND_C to INSN_CLASS_ZCD
Changed INSN_CLASS_ZIHINTNTL_AND_C to INSN_CLASS_ZIHINTNTL_AND_ZCA