ARM: dts: msm: Add SBUx and VPH_PWR channel to pm6150 charger

In SM6150 platforms, channel ADC_SBUx is used for SBU1/2 resistance
measurement by VADC, and channel VPH_PWR for system power input/output
voltage measurement.

Change-Id: I9470e9c5a00b0dfd520152aae7114354c4a6fcba
Signed-off-by: Umang Agrawal <uagrawal@codeaurora.org>