msm: kgsl: Initialize LPAC registers

Some LPAC registers need to be initialized during boot
to avoid any LPAC side glitches at the time when GC is
processing SET_SECURE packets.

Change-Id: Id5ace195cb2e42fdd1661b04a40d3385cbce5635
Signed-off-by: Urvashi Agrawal <urvaagra@codeaurora.org>