In practice, this fixes the issue that if you have an odd number of
mi_cols, on the full right of the image, the UV int4x4 loopfilter
will be skipped over odd cols as well as odd rows (because it holds a
single variable for both edges).
See issue 1016.
Change-Id: Id53b501cbff9323a8239ed4775ae01fe91874b7e
