ARM: dts: msm: Update max bus vote range for Bengal

Existing max bus vote range corresponds to low DDR frequency.
Now when video hardware is made to run at maximum clock and
the max bus vote, DDR is still running at low clock whereas
video hardware runs at max speed.
Update the max bandwidth so as to keep DDR to next corner.

CRs-Fixed: 2858305
Change-Id: Ia20bb6c9ae999bbc75aed627bd200b08fb592bde