ARM: dts: msm: reserve FB memory for continuous splash screen for 8916

Add DT entry to reserve memory needed to display the splash
screen during boot up for 8916. This is needed to enable
continuous splash screen.

Change-Id: I02dd6744d0359a8f53f1cafc632df927d426abfb
Signed-off-by: Padmanabhan Komanduru <pkomandu@codeaurora.org>