[media] trivial: drivers/media/usb/gspca/gspca.h: indent with TABs, not spaces

Signed-off-by: Antonio Ospite <ao2@ao2.it>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>