ARM: dts: msm: Optimize hx8399c panel initialization code

When do panel suspend/resume stress test, panel will
flicker for about 1~2 minutes occasionally. Modified
some initialization parameters for the panel.

Change-Id: Ifd30ed1647a57db78f1e973af205909fdf0718ab
Signed-off-by: Lei Chen <chenlei@codeaurora.org>