drm/msm/dpu: update the qos remap only if the client type changes

Update the qos remap only if the client type changes for the plane.
This will avoid unnecessary register programming and also avoid log
spam from the dpu_vbif_set_qos_remap() function.

changes in v2:
 - get rid of the dirty flag and simplify the logic to call
   _dpu_plane_set_qos_remap()

Signed-off-by: Abhinav Kumar <abhinavk@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>