drm/amdgpu: Fix sdma 4.4.2 doorbell rptr/wptr init

drm/amdgpu: Fix sdma 4.4.2 doorbell rptr/wptr init

Doorbell rptr/wptr can be set through multiple ways including direct
register initialization. Disable doorbell during hw_fini once the ring
is disabled so that during next module reload direct initialization
takes effect. Also, move the direct initialization after minor update is
set to 1 since rptr/wptr are reinitialized back to 0 which could be
lower than the previous doorbell value (ex: cases like module reload).

Signed-off-by: Lijo Lazar <[email protected]>
Reviewed-by: Le Ma <[email protected]>
Reviewed-by: Asad Kamal <[email protected]>
Tested-by: Asad Kamal <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>