[media] Fix undefined reference to `au8522_attach'

au8522_attach is dependent on CONFIG_DVB_AU8522_DTV, not CONFIG_DVB_AU8522.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/dvb-frontends/au8522.h

@@ -61,7 +61,7 @@ struct au8522_config {
 	enum au8522_if_freq qam_if;
 };
 
-#if IS_ENABLED(CONFIG_DVB_AU8522)
+#if IS_ENABLED(CONFIG_DVB_AU8522_DTV)
 extern struct dvb_frontend *au8522_attach(const struct au8522_config *config,
 					  struct i2c_adapter *i2c);
 #else