ARM: dts: msm: Enable the GPU clock driver on MSMCOBALT

Enable support to model the graphics clocks instead of
using dummy clocks. We are still using dummy clocks on
RUMI until the FSM dependencies can be met.

Change-Id: I29b70212f43ddb6ca55b5e985b762bc062bbf266
Signed-off-by: Deepak Katragadda <dkatraga@codeaurora.org>