Move Visitor typedef to <qemu/typedefs.h>

Change-Id: I882fb33701b64982535b9adb1b49ba1cc0d32404

include/qapi/visitor.h

diff --git a/include/qapi/visitor.h b/include/qapi/visitor.h
index 48a2a2e..6b81333 100644
--- a/include/qapi/visitor.h
+++ b/include/qapi/visitor.h
@@ -13,6 +13,7 @@
 #ifndef QAPI_VISITOR_CORE_H
 #define QAPI_VISITOR_CORE_H
 
+#include "qemu/typedefs.h"
 #include "qapi/qmp/qobject.h"
 #include "qapi/error.h"
 #include <stdlib.h>
@@ -26,7 +27,6 @@
     struct GenericList *next;
 } GenericList;
 
-typedef struct Visitor Visitor;
 
 void visit_start_handle(Visitor *v, void **obj, const char *kind,
                         const char *name, Error **errp);

include/qemu/typedefs.h

diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
index a8a7ba8..967a56f 100644
--- a/include/qemu/typedefs.h
+++ b/include/qemu/typedefs.h
@@ -10,6 +10,7 @@
 
 typedef struct AioContext AioContext;
 
+typedef struct Visitor Visitor;
 struct Monitor;
 typedef struct Monitor Monitor;
 typedef struct MigrationParams MigrationParams;