target/riscv: Move cpu_get_tb_cpu_state out of line

target/riscv: Move cpu_get_tb_cpu_state out of line

Move the function to cpu_helper.c, as it is large and growing.

Reviewed-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20211020031709.359469-2-richard.henderson@linaro.org
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>