disp: msm: sde: add kickoff_in_progress flag in sde crtc

In dual display usecases, during pm suspend/resume,
commit is scheduled only on primary crtc thread. If idle
timeout value is very short such as in LP2 mode, it might
result in race condition due to idle pc off work getting
scheduled on its crtc thread. This change adds kickoff in
progress flag to handle such cases as crtc frame pending
count is only updated after rc kickoff.

Change-Id: Iebb331d914b23cc5eeadfeb2a488891e88b3202a
Signed-off-by: Yashwanth <yvulapu@codeaurora.org>