usb: gadget: nokia: remove unused include

f_serial.c isn't necessary in nokia.c, we can
safely remove it.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
1 file changed