msm: mdss: Fix tearing and hang issues for autorefresh

While turning off autorefresh feature, there are some frames
that do not get transmitted causing timeouts. This change gracefully
exits autorefresh feature while new frames are pushed.

Crs-Fixed: 773221
Change-Id: I66ecf13133723ff5fad465755d50c6eb1ec0e52a
Signed-off-by: Siddhartha Agrawal <agrawals@codeaurora.org>
Signed-off-by: Ujwal Patel <ujwalp@codeaurora.org>