[media] dvb-frontends: use IS_ENABLED

Instead of checking everywhere there for 3 symbols, use instead
IS_ENABLED macro.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/dvb-frontends/dvb_dummy_fe.h b/drivers/media/dvb-frontends/dvb_dummy_fe.h
index 1fcb987..0cbf961 100644
--- a/drivers/media/dvb-frontends/dvb_dummy_fe.h
+++ b/drivers/media/dvb-frontends/dvb_dummy_fe.h
@@ -22,11 +22,11 @@
 #ifndef DVB_DUMMY_FE_H
 #define DVB_DUMMY_FE_H
 
+#include <linux/kconfig.h>
 #include <linux/dvb/frontend.h>
 #include "dvb_frontend.h"
 
-#if defined(CONFIG_DVB_DUMMY_FE) || (defined(CONFIG_DVB_DUMMY_FE_MODULE) && \
-defined(MODULE))
+#if IS_ENABLED(CONFIG_DVB_DUMMY_FE)
 extern struct dvb_frontend* dvb_dummy_fe_ofdm_attach(void);
 extern struct dvb_frontend* dvb_dummy_fe_qpsk_attach(void);
 extern struct dvb_frontend* dvb_dummy_fe_qam_attach(void);