ARM: dts: msm: Add GPU properties for Cobalt

Add device specific GPU properties for Cobalt.
Add GPU DCVS and bus DCVS plan

CR-fixed: 973565
Change-Id: I6c51be7eeb50c41d4cfa9f9548ebd48888ee1ac5
Signed-off-by: Lokesh Batra <lbatra@codeaurora.org>
Signed-off-by: George Shen <sqiao@codeaurora.org>
Signed-off-by: Oleg Perelet <operelet@codeaurora.org>