ARM: dts: msm: Add GPU speed config support to MSM8916

'gpu-speed-config' property helps driver to load the
dynamic power level and bus scale setting supports
based on the speed bin configuration. This makes MSM8916
to support 465Mhz GPU clock and DDR max vote to 595.2Mhz.

Change-Id: I18c89b357d25618c4f1da746032ecf70bedcfeb7
Signed-off-by: Hareesh Gundu <hareeshg@codeaurora.org>
Signed-off-by: Bharat Pawar <bpawar@codeaurora.org>
Signed-off-by: Nirmal Abraham <nabrah@codeaurora.org>