target/riscv: Add cycle & instret privilege mode filtering definitions

target/riscv: Add cycle & instret privilege mode filtering definitions

This adds the definitions for ISA extension smcntrpmf.

Signed-off-by: Kaiwen Xue <kaiwenx@rivosinc.com>
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: <20240711-smcntrpmf_v7-v8-4-b7c38ae7b263@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>