target/riscv: Remove the hardcoded HGATP_MODE macro

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Message-id: 665f624bfdc2e3ca64265004b07de7489c77a766.1619234854.git.alistair.francis@wdc.com
2 files changed