msm: kgsl: Add support for A680 GPU

Add new GPU ID and initial settings, to support
graphics on sdmshrike.

Change-Id: I16f74545196909430773b8ca242f91df7e35c73b
Signed-off-by: Urvashi Agrawal <urvaagra@codeaurora.org>
Signed-off-by: Lokesh Batra <lbatra@codeaurora.org>