ARM: dts: msm: Add INA231 for MSM8996 fluid

INA231 driver communicates over I2C and clients can use it
to read bus voltage which is vph_pwr and shunt voltage drop
across a 5mohm shunt resistor.

Change-Id: I1b2d7eb27ab11bd9d7d7a8291a45f1e76da3bb34
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>