msm: mdss: add panel on command support after te enable

Few DSI panels has requirement of receiving display on command
after receiving sleep out command and pixel stream data. This
can be achieved by sending panel post on command followed by
timing engine enable. This change adds the support for such
kind of DSI panels.

Change-Id: Ifa225aec4ad9bfd692e19c02bcb726c8d60ce4fb
Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>
Signed-off-by: Sachin Bhayare <sachin.bhayare@codeaurora.org>