dwc3: gadget: Don't resume controller when charger is connected

dwc3_gadget_start() API is being called when android gadget driver
is binding with UDC driver. The purpose of this API to update
gadget_driver with UDC only. It doesn't need any register read/write
access when it is being non DRD mode. Hence remove resuming controller
only in non DRD mode.

Change-Id: I5fab313b24c92f1c9cc0b4d7493758e91e92657c
Signed-off-by: Mayank Rana <mrana@codeaurora.org>