Fix xen build after sys-queue renaming

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/hw/xen_common.h b/hw/xen_common.h
index 7562567..8a55b44 100644
--- a/hw/xen_common.h
+++ b/hw/xen_common.h
@@ -10,7 +10,7 @@
 
 #include "hw.h"
 #include "xen.h"
-#include "sys-queue.h"   /* BSD list implementation */
+#include "qemu-queue.h"
 
 /*
  * tweaks needed to build with different xen versions