[media] gspca - jeilinj: use gspca_dev->usb_err to forward error to upper layer

Signed-off-by: Patrice CHOTARD <patricechotard@free.fr>
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>