Move the SDMA workaround necessary for Navi 1x into a higher layer.

v2: use dev_err
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>