adreno_tz: Use context aware dcvs calls, if available

Add support to use context aware dcvs, if it is supported
by TZ. Context aware dcvs helps in handling sudden workload
scenarios.

Change-Id: I5e6e6003a5c61eacb4f5af91910994919a5a7684
Signed-off-by: Deepak Kumar <dkumar@codeaurora.org>
Signed-off-by: Divya Ponnusamy <pdivya@codeaurora.org>