ARM: dts: msm: Update graphics vdd restriction level for MSM8996v3

Update with the correct nominal voltage level for graphics
rail for MSM8996v3. At low temperatures, thermal will
restrict the graphics rail to the new nominal level for
MSM8996 v3.

Change-Id: Idfc9b5d18b6ba130506f15e935f99854f383765d
Signed-off-by: Ram Chandrasekar <rkumbako@codeaurora.org>