define MAP_ANONYMOUS if it is not defined in qemu-common.h

Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/qemu-common.h b/qemu-common.h
index 6a15f89..671c0fc 100644
--- a/qemu-common.h
+++ b/qemu-common.h
@@ -32,7 +32,9 @@
 #ifndef O_BINARY
 #define O_BINARY 0
 #endif
-
+#ifndef MAP_ANONYMOUS
+#define MAP_ANONYMOUS MAP_ANON
+#endif
 #ifndef ENOMEDIUM
 #define ENOMEDIUM ENODEV
 #endif