usb: gadget: udc: atmel_usba_udc: Remove set but unused variable 'pp'

usb: gadget: udc: atmel_usba_udc: Remove set but unused variable 'pp'

Commit e78355b577c4b ("usb: gadget: udc: atmel: Don't use DT to
configure end point") pulled out all functionality dealing with 'pp'.

Fixes the following W=1 kernel build warning(s):

 drivers/usb/gadget/udc/atmel_usba_udc.c: In function ‘atmel_udc_of_init’:
 drivers/usb/gadget/udc/atmel_usba_udc.c:2106:22: warning: variable ‘pp’ set but not used [-Wunused-but-set-variable]
 2106 | struct device_node *pp;
 | ^~

Cc: Cristian Birsan <cristian.birsan@microchip.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20200706133341.476881-10-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>