msm: mdss: control backlight level during blank and unblank events

Add code to set the backlight level to zero for blank event
and restore the backlight level to its previous value during
unblank event. This will fix any unexpected panel flicker
that might show up on the screen during panel ON sequence.

CRs-Fixed: 608091
Change-Id: I871a067b0cc40d893b8b7e5a25103ebb914f9b7a
Signed-off-by: Chandan Uddaraju <chandanu@codeaurora.org>
Signed-off-by: Benet Clark <benetc@codeaurora.org>
mdss: Dynamic timeout calculation for cmd stop

Time out condition was hard coded to 60 fps. If dynamic fps
feature was used, an invalid timeout might occur.

Change-Id: I0abe52416c10ef4ae0af6f541d22c66f6c8a6b5e
Signed-off-by: Terence Hampson <thampson@codeaurora.org>