Revert "clk: msm: clock-gpu-cobalt: Update the graphics core clock frequency"

This reverts commit bfebb79e ("clk: msm: clock-gpu-cobalt:
Update the graphics core clock frequency") since we now want
to enable scaling the graphics core clock upto 710 MHz on
MSMCOBALT v2.

Change-Id: I2715197a2b5cbe41da5b1983ff3066fa5d42c483
Signed-off-by: Deepak Katragadda <dkatraga@codeaurora.org>