msm: kgsl: Add opp table to bus monitor device

Devfreq driver expects a opp table to be be part of the
device. So add the gpu opp table to register the devfreq
device for gpu bus dcvs.

Change-Id: I6ca6e29e2a7f3c22227dcd6490061eaf169e8a80
Signed-off-by: Harshdeep Dhatt <hdhatt@codeaurora.org>