extcon: usb-gpio: Don't miss event during suspend/resume

Pin state might have changed during suspend/resume while
our interrupts were disabled and if device doesn't support wakeup.

Scan for change during resume for such case.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>