Using KIQ to map GFX queues instead of MMIO for gfx async ring,
add missing doorbell range setting.

v2: fix typo
Signed-off-by: Jinzhou.Su <Jinzhou.Su@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>