arm/dt: msm8974: enable SMBB otg and boost regulators

Add two regulators for the pm8941_chg device container.
One to control the OTG FET, as well as one to support
the SMBB_BOOST peripheral.

The pm8941_chg_otg regulator is set as the parent
supply of pm8941_mvs1. This ensures that the OTG OVP
FET is turned on before the OTG switch is enabled.

CRs-Fixed: 486088
Change-Id: Ife6e1a39bcfb0fd6655a344ffecf7e7ff122dff1
Signed-off-by: David Keitel <dkeitel@codeaurora.org>