ARM: dts: msm: enable default panel for 8994

Include the default panel files for CDP and
MTP variants. Add pinctrl support on 8994 to
configure the needed gpios.

Add corresponding gpios and backlight
control that are needed to enable the panel.

Change-Id: I0f22ce71623532734926c95483a4ce3f0191d2c3
Signed-off-by: Chandan Uddaraju <chandanu@codeaurora.org>