target/riscv: correct csr_ops[CSR_MSECCFG]

target/riscv: correct csr_ops[CSR_MSECCFG]

The CSR register mseccfg is used by multiple extensions: Smepm and Zkr.

Consider this when checking the existence of the register.

Fixes: 77442380ecbe ("target/riscv: rvk: add CSR support for Zkr")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20231030102105.19501-1-heinrich.schuchardt@canonical.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>