drm/msm/sde: enable intf misr after frame trigger

Perform MISR enable after frame trigger and then collect misr after misr
status bit is set. Previously misr was enabled through debugfs, so if
system goes into idle power collapse before commit, then misr enable
status was not retained. Also it was not waiting for misr status bit.

Change-Id: I36f638845af9b67cf67f3719a0254f82b06d33ae
Signed-off-by: Gurpreet Singh Dhami <gdhami@codeaurora.org>