[media] gp8psk: make local symbol gp8psk_fe_ops static

Fixes the following sparse warning:

drivers/media/usb/dvb-usb/gp8psk.c:281:28: warning:
 symbol 'gp8psk_fe_ops' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/usb/dvb-usb/gp8psk.c

@@ -278,7 +278,7 @@ static int gp8psk_fe_reload(void *priv)
 	return gp8psk_bcm4500_reload(d);
 }
 
-const struct gp8psk_fe_ops gp8psk_fe_ops = {
+static const struct gp8psk_fe_ops gp8psk_fe_ops = {
 	.in = gp8psk_fe_in,
 	.out = gp8psk_fe_out,
 	.reload = gp8psk_fe_reload,