migration: move include files to include/migration/

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/include/net/net.h b/include/net/net.h
index 26dd0cf..41d3729 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -6,7 +6,7 @@
 #include "qapi/qmp/qdict.h"
 #include "qemu-option.h"
 #include "net/queue.h"
-#include "vmstate.h"
+#include "migration/vmstate.h"
 #include "qapi-types.h"
 
 struct MACAddr {