[media] dvb-usb/dvb-usb-v2: 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/usb/dvb-usb-v2/mxl111sf-demod.h b/drivers/media/usb/dvb-usb-v2/mxl111sf-demod.h
index 432706a..3f3f8bf 100644
--- a/drivers/media/usb/dvb-usb-v2/mxl111sf-demod.h
+++ b/drivers/media/usb/dvb-usb-v2/mxl111sf-demod.h
@@ -21,6 +21,7 @@
 #ifndef __MXL111SF_DEMOD_H__
 #define __MXL111SF_DEMOD_H__
 
+#include <linux/kconfig.h>
 #include "dvb_frontend.h"
 #include "mxl111sf.h"
 
@@ -31,8 +32,7 @@
 			    struct mxl111sf_reg_ctrl_info *ctrl_reg_info);
 };
 
-#if defined(CONFIG_DVB_USB_MXL111SF) || \
-	(defined(CONFIG_DVB_USB_MXL111SF_MODULE) && defined(MODULE))
+#if IS_ENABLED(CONFIG_DVB_USB_MXL111SF)
 extern
 struct dvb_frontend *mxl111sf_demod_attach(struct mxl111sf_state *mxl_state,
 					   struct mxl111sf_demod_config *cfg);