qcom: smb1355: introduction of smb1355 driver

This driver supports the SMB1355, as a slave charger device, to be
paired with QTI's standalone chargers.

Register access is provided by the parent device via regmap. Interrupts
are controlled by the parent device, and handlers are registered by the
SMB1355 charger driver.

The power supply framework is used to communicate battery and usb
properties to userspace and other driver consumers such as fuel gauge
and USB.

Change-Id: I74f283ac1547ee8ce76150c64d8bbbed2efeeb0c
Signed-off-by: Harry Yang <harryy@codeaurora.org>