[media] dvb-core: add support for a DVBv5 get_frontend() callback

Creates a DVBv5 get_frontend call, renaming the DVBv3 one to
get_frontend_legacy(), while not all frontends are converted.

After the conversion for all drivers, get_frontend_legacy()
will be removed.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/dvb/frontends/dvb_dummy_fe.c b/drivers/media/dvb/frontends/dvb_dummy_fe.c
index 322bcd7..31e1dd6 100644
--- a/drivers/media/dvb/frontends/dvb_dummy_fe.c
+++ b/drivers/media/dvb/frontends/dvb_dummy_fe.c
@@ -193,7 +193,7 @@
 	.sleep = dvb_dummy_fe_sleep,
 
 	.set_frontend_legacy = dvb_dummy_fe_set_frontend,
-	.get_frontend = dvb_dummy_fe_get_frontend,
+	.get_frontend_legacy = dvb_dummy_fe_get_frontend,
 
 	.read_status = dvb_dummy_fe_read_status,
 	.read_ber = dvb_dummy_fe_read_ber,
@@ -223,7 +223,7 @@
 	.sleep = dvb_dummy_fe_sleep,
 
 	.set_frontend_legacy = dvb_dummy_fe_set_frontend,
-	.get_frontend = dvb_dummy_fe_get_frontend,
+	.get_frontend_legacy = dvb_dummy_fe_get_frontend,
 
 	.read_status = dvb_dummy_fe_read_status,
 	.read_ber = dvb_dummy_fe_read_ber,
@@ -255,7 +255,7 @@
 	.sleep = dvb_dummy_fe_sleep,
 
 	.set_frontend_legacy = dvb_dummy_fe_set_frontend,
-	.get_frontend = dvb_dummy_fe_get_frontend,
+	.get_frontend_legacy = dvb_dummy_fe_get_frontend,
 
 	.read_status = dvb_dummy_fe_read_status,
 	.read_ber = dvb_dummy_fe_read_ber,