target/riscv: Add support for Zce

target/riscv: Add support for Zce

Add and expose property for Zce:
* Specifying Zce without F includes Zca, Zcb, Zcmp, Zcmt.
* Specifying Zce with F includes Zca, Zcb, Zcmp, Zcmt and Zcf.

Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230307081403.61950-11-liweiwei@iscas.ac.cn>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>