msm: mdss: add support for rotator in mdss_mdp_mixer_get

Currently ctl->mfd is not populated for rotator sessions. If
mdss_mdp_mixer_get is called by rotator session then it will always
fail the NULL check for ctl->mfd. This will flood the logs for every
rotator commit and can lead to un-predictable outcome. Fix this by
properly handling rotator case in mdss_mdp_mixer_get.

Change-Id: Ib1896149302bd60b99028ae26df2393fab30dd6e
Signed-off-by: Ujwal Patel <ujwalp@codeaurora.org>
msm: mdss: fix sync fence deadlock when rotator is used

In the current implementation, whenever rotator play is called, it
forces DMA pipes to be released by calling commit on video mode ctl
paths if they are using DMA pipes. Here assumption was that DMA pipes
will either be used in block mode or line mode, all or none. But this
assumption is not valid any more where we can have a use-case where
DMA0 is used for rotator and DMA1 for video mode ctl path. In this
use-case, current implementation can lead to sync fence deadlock. Fix
this by removing obsolete assumption.

Change-Id: I2d1da9dca5d958257796d617db11d93631c98f27
CRs-Fixed: 656463
Signed-off-by: Ujwal Patel <ujwalp@codeaurora.org>
(cherry picked from commit 1f3710b6b90753ee4670cc1ad009f6f763b8fbf2)