extcon: intel-mrfld: Sync hardware and software state on init

extcon driver for Basin Cove PMIC shadows the switch status used for dwc3
DRD to detect a change in the switch position. This change initializes the
status at probe time.

Cc: stable@vger.kernel.org
Fixes: 492929c5 ("extcon: mrfld: Introduce extcon driver for Basin Cove PMIC")
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ferry Toth <ftoth@exalondelft.nl>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>