ARM: dts: msm: Update the L3 GPU vote for sm8150 v2

The L3 clock can run at a higher frequency on sm8150 v2. Update the
L3 GPU vote to take advantage of the higher frequency.

Change-Id: I3bb9f8c66be231391a2c072859d4e0e58906ac14
Signed-off-by: Lynus Vaz <lvaz@codeaurora.org>