msm: kgsl: Add A6XX powerup register list

On A6XX, we need to specify a list of register offset
-value pairs along with the CP_INIT packet. This is needed
because CP will execute these writes at the time of
preemption.

Change-Id: Iec6240cb0ec4c0a6264ec063155002ed7d8d2151
Signed-off-by: Harshdeep Dhatt <hdhatt@codeaurora.org>