ARM: dts: msm: Update core frequencies for vmem plus governor

The venus core nominal and turbo frequencies have changed
from 355 Mhz and 533 Mhz to 346 Mhz and 520 Mhz respectively.
The imem-ab-tbl used by vmem plus governor for vmem ab
calculation needs to be updated with the new venus core
frequencies. Without this change, the vmem clock scaling
will be incorrect and will hit performance issues.

Change-Id: I09796a8745d982a831ef8bc4fe8e57c68d6ceffb
Signed-off-by: Arun Menon <avmenon@codeaurora.org>