drm/amdgpu: enable Navi12 kfd support for amdgpu

Navi12 has the same interface as Navi10

Signed-off-by: shaoyunl <shaoyun.liu@amd.com>
Reviewed-by: Jack Xiao <Jack.Xiao@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>