[media] dvb core: rename the media controller entities

Prefix all DVB media controller entities with "dvb-" and use dash
instead of underline at the names.

Requested-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

diff --cc drivers/media/dvb-core/dmxdev.c
Simple merge

diff --cc drivers/media/dvb-core/dvb_ca_en50221.c
Simple merge

diff --cc drivers/media/dvb-core/dvb_net.c
Simple merge