Fix warnings

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6346 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/console.c b/console.c
index a37edf7..3950d20 100644
--- a/console.c
+++ b/console.c
@@ -1190,7 +1190,8 @@
     }
 }
 
-static TextConsole *get_graphic_console() {
+static TextConsole *get_graphic_console(void)
+{
     int i;
     TextConsole *s;
     for (i = 0; i < nb_consoles; i++) {