dt-bindings: power: supply: bq24190_charger: add bq24192 and usb-otg-vbus

Add support for the ti,bq24192 variant and a child node for the
usb-otg-vbus regulator.

Signed-off-by: Brian Masney <masneyb@onstation.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>