power: smb1351-charger: add support for recovering from USB over voltage

The current driver indicates usb removal on a USB OV event.
There is also a need to notify usb insertion when charger
voltage back to normal.

In the meantime, fix a bug for the conflict between USB OV
interrupt and source detect interrupt by adding a USB OV check
in source detect interrupt handler.

CRs-Fixed: 841380
Change-Id: I3ef881552cfe610cace1ed438a7b85f06cacc11f
Signed-off-by: Zhenhua Huang <zhenhuah@codeaurora.org>