msm: kgsl: Create Adreno family for A640, A650 and A680

The changes needed for A640 mostly apply to A650 and A680 as well,
create a family for these 3 so that we don't have to keep adding
separate checks for them.

Change-Id: I846b645aee5dcfd4a5dfbdaef2dffb8a1dc990af
Signed-off-by: Urvashi Agrawal <urvaagra@codeaurora.org>