media: dvb_frontends: fix kernel-doc macros

Now, the Kernel checks for kernel_doc format issues.
Weird enough, it didn't get any of those troubles. Shssst!

Well, let's fix it, as a preventive way to avoid having
hundreds of new warnings on some next Linux version.

Tested by adding all files under dvb-frontends that have
"/**" on them.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/dvb-frontends/tda826x.h

@@ -29,11 +29,12 @@
 /**
  * Attach a tda826x tuner to the supplied frontend structure.
  *
- * @param fe Frontend to attach to.
- * @param addr i2c address of the tuner.
- * @param i2c i2c adapter to use.
- * @param has_loopthrough Set to 1 if the card has a loopthrough RF connector.
- * @return FE pointer on success, NULL on failure.
+ * @fe: Frontend to attach to.
+ * @addr: i2c address of the tuner.
+ * @i2c: i2c adapter to use.
+ * @has_loopthrough: Set to 1 if the card has a loopthrough RF connector.
+ *
+ * return: FE pointer on success, NULL on failure.
  */
 #if IS_REACHABLE(CONFIG_DVB_TDA826X)
 extern struct dvb_frontend* tda826x_attach(struct dvb_frontend *fe, int addr,