msm: mdss: add dynamic clk status check to pipe idle verification

Dynamic clk status of pipe can indicate if that pipe is active or not.
This status in conjunction VBIF halt status of pipe describes the idle
state of the pipe. Add support to parse necessary offsets from DT and
use them to find idle state of the pipe.

Change-Id: I83c6f323d48a85bfc08ff7bcee47f7c3038ea7e1
Signed-off-by: Ujwal Patel <ujwalp@codeaurora.org>
msm: mdss: delay freeing buffers for additional vsync

There are cases where if commit happens very close to vsync or in other
uncommon conditions, where MDP will continue fetching from old buffer
address when unmap of the buffer happens. In order to avoid such
scenarios keep a reference of buffers for an additional commit before
unmapping to avoid potential iommu page fault.

Change-Id: Ied61b4851e2d410d71360ad0c119ef21009f91a1
Signed-off-by: Adrian Salido-Moreno <adrianm@codeaurora.org>