staging: line6: eliminate useless NULL checks

The line6 driver checks struct field addresses for NULL where it does
not make sense to do so.  The struct has already been checked for NULL
and there is no value in checking the first field's address too.
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Markus Grabner <grabner@icg.tugraz.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/line6/pod.c

@@ -1149,14 +1149,10 @@ static struct snd_kcontrol_new pod_control_monitor = {
 static void pod_destruct(struct usb_interface *interface)
 {
 	struct usb_line6_pod *pod = usb_get_intfdata(interface);
-	struct usb_line6 *line6;
 
 	if (pod == NULL)
 		return;
-	line6 = &pod->line6;
-	if (line6 == NULL)
-		return;
-	line6_cleanup_audio(line6);
+	line6_cleanup_audio(&pod->line6);
 
 	del_timer(&pod->startup_timer);
 	cancel_work_sync(&pod->startup_work);

drivers/staging/line6/podhd.c

@@ -80,14 +80,10 @@ static struct line6_pcm_properties podhd_pcm_properties = {
 static void podhd_destruct(struct usb_interface *interface)
 {
 	struct usb_line6_podhd *podhd = usb_get_intfdata(interface);
-	struct usb_line6 *line6;
 
 	if (podhd == NULL)
 		return;
-	line6 = &podhd->line6;
-	if (line6 == NULL)
-		return;
-	line6_cleanup_audio(line6);
+	line6_cleanup_audio(&podhd->line6);
 }
 
 /*

drivers/staging/line6/toneport.c

@@ -295,14 +295,10 @@ static struct snd_kcontrol_new toneport_control_source = {
 static void toneport_destruct(struct usb_interface *interface)
 {
 	struct usb_line6_toneport *toneport = usb_get_intfdata(interface);
-	struct usb_line6 *line6;
 
 	if (toneport == NULL)
 		return;
-	line6 = &toneport->line6;
-	if (line6 == NULL)
-		return;
-	line6_cleanup_audio(line6);
+	line6_cleanup_audio(&toneport->line6);
 }
 
 /*

drivers/staging/line6/variax.c

@@ -572,14 +572,10 @@ static DEVICE_ATTR(raw2, S_IWUSR, line6_nop_read, variax_set_raw2);
 static void variax_destruct(struct usb_interface *interface)
 {
 	struct usb_line6_variax *variax = usb_get_intfdata(interface);
-	struct usb_line6 *line6;
 
 	if (variax == NULL)
 		return;
-	line6 = &variax->line6;
-	if (line6 == NULL)
-		return;
-	line6_cleanup_audio(line6);
+	line6_cleanup_audio(&variax->line6);
 
 	del_timer(&variax->startup_timer1);
 	del_timer(&variax->startup_timer2);