ARM: dts: Update the initial power level for SM6150 GPU

Update the initial power level to wake up gpu at low svs for all speed
bins of SM6150 gpu to meet the power requirement.

Change-Id: I02c1260b5ada8d409137aa9c173138bf65744345
Signed-off-by: Akhil P Oommen <akhilpo@codeaurora.org>