[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/a8293.h b/drivers/media/dvb-frontends/a8293.h
index ed29e55..b6ef642 100644
--- a/drivers/media/dvb-frontends/a8293.h
+++ b/drivers/media/dvb-frontends/a8293.h
@@ -21,12 +21,13 @@
 #ifndef A8293_H
 #define A8293_H
 
+#include <linux/kconfig.h>
+
 struct a8293_config {
 	u8 i2c_addr;
 };
 
-#if defined(CONFIG_DVB_A8293) || \
-	(defined(CONFIG_DVB_A8293_MODULE) && defined(MODULE))
+#if IS_ENABLED(CONFIG_DVB_A8293)
 extern struct dvb_frontend *a8293_attach(struct dvb_frontend *fe,
 	struct i2c_adapter *i2c, const struct a8293_config *cfg);
 #else