usb: gadget: pch_udc: Initialize device pointer before use

usb: gadget: pch_udc: Initialize device pointer before use

During conversion to use GPIO descriptors the device pointer,
which is applied to devm_gpiod_get(), is not yet initialized.

Move initialization in the ->probe() in order to have it set before use.

Fixes: e20849a8c883 ("usb: gadget: pch_udc: Convert to use GPIO descriptors")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210323153626.54908-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>