power: smb1351: set correct usb mode polarity when in parallel mode

Currently, the smb1351 driver does not set the same USB100/USB500 mode
polarity when ran in parallel mode. This can cause current limits of
500/900mA to be switched with 100/150mA.

Fix this by setting the same bits the smb1351 does in its normal hw_init
routine.

CRs-Fixed: 877809
Change-Id: I44ae3086fd86e46b15a2c16368fcd5aade771319
Signed-off-by: Xiaozhe Shi <xiaozhes@codeaurora.org>