dialog: export new itermodule api functions

- get duplicate var value and status

src/modules/dialog/dialog.c

@@ -483,6 +483,8 @@ int load_dlg( struct dlg_binds *dlgb )
 	dlgb->set_dlg_var = set_dlg_variable;
 	dlgb->get_dlg_varref = get_dlg_varref;
 	dlgb->get_dlg_varval = get_dlg_varval;
+	dlgb->get_dlg_vardup = get_dlg_vardup;
+	dlgb->get_dlg_varstatus = get_dlg_varstatus;
 	dlgb->get_dlg = dlg_get_msg_dialog;
 	dlgb->release_dlg = dlg_release;
 	return 1;

src/modules/dialog/dlg_load.h

@@ -43,14 +43,15 @@ typedef struct dlg_cell *(*get_dlg_f)(struct sip_msg *msg);
 typedef void (*release_dlg_f)(struct dlg_cell *dlg);
 
 struct dlg_binds {
-	register_dlgcb_f  register_dlgcb;
-	terminate_dlg_f terminate_dlg;
-    set_dlg_variable_f set_dlg_var;
-	get_dlg_varref_f   get_dlg_varref;
-	get_dlg_varval_f   get_dlg_varval;
-	get_dlg_vardup_f   get_dlg_vardup;
-	get_dlg_f          get_dlg;
-	release_dlg_f      release_dlg;
+	register_dlgcb_f    register_dlgcb;
+	terminate_dlg_f     terminate_dlg;
+	set_dlg_variable_f  set_dlg_var;
+	get_dlg_varref_f    get_dlg_varref;
+	get_dlg_varval_f    get_dlg_varval;
+	get_dlg_vardup_f    get_dlg_vardup;
+	get_dlg_varstatus_f get_dlg_varstatus;
+	get_dlg_f           get_dlg;
+	release_dlg_f       release_dlg;
 };