lib: use app-icon-name for libvlc_set_app_id

(cherry picked from commit 67e74ed283db585fb8ee7905a877117fbde1932d)
Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

lib/core.c

@@ -154,7 +154,7 @@ void libvlc_set_app_id(libvlc_instance_t *p_i, const char *id,
 
     var_SetString(p_libvlc, "app-id", id ? id : "");
     var_SetString(p_libvlc, "app-version", version ? version : "");
-    var_SetString(p_libvlc, "app-version", icon ? icon : "");
+    var_SetString(p_libvlc, "app-icon-name", icon ? icon : "");
 }
 
 const char * libvlc_get_version(void)