msm: mdss: release rotator bandwidth once rotator finished processing

Once rotator finished processing the data, the bandwidth for the
rotator can be removed from the bandwidth vote. This change remove
the rotator bandwidth from the vote after rotator completed the
transaction.

Change-Id: Ic79398006a1514c4b422e8b3aa7cafcb7fb3c002
Signed-off-by: Ingrid Gallardo <ingridg@codeaurora.org>
Signed-off-by: Jayant Shekhar <jshekhar@codeaurora.org>