ASoC: hdac_hdmi: don't update the iterator in pcm list remove

Fix not to update the iterator element, instead use list_del to remove
entry from the list.

This fixes the following coccinelle and static checker warning:
sound/soc/codecs/hdac_hdmi.c:1884:2-21:iterator with update on line
1885
sound/soc/codecs/hdac_hdmi.c:2011 hdac_hdmi_dev_remove()
	error: potential NULL dereference 'port'.

Fixes: e0e5d3e5('ASoC: hdac_hdmi: Add support for multiple ports to a PCM')
Reported-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/hdac_hdmi.c

@@ -1997,7 +1997,7 @@ static int hdac_hdmi_dev_remove(struct hdac_ext_device *edev)
 	struct hdac_hdmi_pin *pin, *pin_next;
 	struct hdac_hdmi_cvt *cvt, *cvt_next;
 	struct hdac_hdmi_pcm *pcm, *pcm_next;
-	struct hdac_hdmi_port *port;
+	struct hdac_hdmi_port *port, *port_next;
 	int i;
 
 	snd_soc_unregister_codec(&edev->hdac.dev);
@@ -2007,8 +2007,9 @@ static int hdac_hdmi_dev_remove(struct hdac_ext_device *edev)
 		if (list_empty(&pcm->port_list))
 			continue;
 
-		list_for_each_entry(port, &pcm->port_list, head)
-			port = NULL;
+		list_for_each_entry_safe(port, port_next,
+					&pcm->port_list, head)
+			list_del(&port->head);
 
 		list_del(&pcm->head);
 		kfree(pcm);