msm: kgsl: Use main wait_event macros instead of helper

Currently, we seem to be using the helper functions for the
wait_event APIs in our code. Replace these with the main
wait_event APIs since these are consistent over different kernels
whereas the helper functions can change.

Change-Id: I76ee1ef49f807271e96c6fb77278e4ab581adf0d
Signed-off-by: Shrenuj Bansal <shrenujb@codeaurora.org>