target/riscv: Replace cpu_mmu_index with riscv_env_mmu_index

Use the target-specific function name in preference
to the generic name.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
3 files changed