target/riscv: Add properties for counter delegation ISA extensions

target/riscv: Add properties for counter delegation ISA extensions

This adds the properties for counter delegation ISA extensions
(Smcdeleg/Ssccfg). Definitions of new registers and and implementation
will come in the next set of patches.

Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20250110-counter_delegation-v5-5-e83d797ae294@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>