File fix-serious-gcc-warnings of Package fprint_demo

Index: fprint_demo-0.4/src/enroll.c
===================================================================
--- fprint_demo-0.4.orig/src/enroll.c
+++ fprint_demo-0.4/src/enroll.c
@@ -160,6 +160,7 @@ static GtkWidget *edlg_show(GtkWidget *w
 	edlg_enroll_data = NULL;
 	enroll_stage = 1;
 	edlg_run_enroll_stage();
+	return 0;
 }
 
 static GtkWidget *edlg_create(int fnum)
Index: fprint_demo-0.4/src/main.c
===================================================================
--- fprint_demo-0.4.orig/src/main.c
+++ fprint_demo-0.4/src/main.c
@@ -54,6 +54,7 @@ static gboolean mwin_cb_tab_changed(GtkN
 	GtkNotebookPage *page, guint tabnum, gpointer data)
 {
 	const struct fpd_tab *tab = tabs[tabnum];
+	return 0;
 }
 
 static void mwin_devstatus_update(char *status)