V4L/DVB (13294): dvb-usb-friio: cleaning up unnecessary functions

This patch removes some fe->ops.X() functions which do nothing more useful than the default.

Signed-off-by: Akihiro Tsukada <tskd2@yahoo.co.jp>
Signed-off-by: Douglas Schilling Landgraf <dougsland@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>