ARM: dts: msm: Reorder GMU power levels on SDM670

The GMU needs to receive the GMU power levels in the
order lowest to highest. Reverse the order in the DTSI
file for SDM670.

Change-Id: I6455666666fa15d4b7c3f8eb53a4443ed0106e5f
Signed-off-by: Deepak Kumar <dkumar@codeaurora.org>