power_supply: Add driver for TWL4030/TPS65950 BCI charger

TWL4030/TPS65950 is a multi-function device with integrated charger,
which allows charging from AC or USB. This driver enables the charger
and provides several monitoring functions.

Tested on OMAP3 Pandora board.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>