[libgnome-volume-control/wip/muktupavels/warnings: 3/3] mixer-stream: fix cast-function-type warning

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 001c3baa1707c1df311e57c0aed34139db168141
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Sun Sep 9 00:01:08 2018 +0300

    mixer-stream: fix cast-function-type warning

 gvc-mixer-stream.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)
---
diff --git a/gvc-mixer-stream.c b/gvc-mixer-stream.c
index 5de71d1..151961a 100644
--- a/gvc-mixer-stream.c
+++ b/gvc-mixer-stream.c
@@ -110,6 +110,13 @@ dup_port (GvcMixerStreamPort *p)
 
 G_DEFINE_BOXED_TYPE (GvcMixerStreamPort, gvc_mixer_stream_port, dup_port, free_port)
 
+static void
+list_free_port (GvcMixerStreamPort *p,
+                gpointer            user_data)
+{
+        free_port (p);
+}
+
 static guint32
 get_next_stream_serial (void)
 {
@@ -1038,7 +1045,7 @@ gvc_mixer_stream_finalize (GObject *object)
         g_free (mixer_stream->priv->human_port);
         mixer_stream->priv->human_port = NULL;
 
-        g_list_foreach (mixer_stream->priv->ports, (GFunc) free_port, NULL);
+        g_list_foreach (mixer_stream->priv->ports, (GFunc) list_free_port, NULL);
         g_list_free (mixer_stream->priv->ports);
         mixer_stream->priv->ports = NULL;