[libxml2] dict.h: gcc 2.95 doesn't allow multiple storage classes

[Nick Wellnhofer <nwellnhof src gnome org>]

commit 37189c08e61ee90e6a1e46276ac724decf467a4b
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Mon Jul 8 12:18:24 2019 +0200

    dict.h: gcc 2.95 doesn't allow multiple storage classes
    
    This is a partial revert of commit c71f9305. I'm not sure what issue
    this commit was trying to solve but it seems to be related to a
    circular dependency. It might be related to tree.h being included
    from dict.h which is unnecessary.
    
    Resolves !22.

 doc/apibuild.py       |  1 -
 include/libxml/dict.h | 19 ++++++-------------
 2 files changed, 6 insertions(+), 14 deletions(-)
---
diff --git a/doc/apibuild.py b/doc/apibuild.py
index 7c69a537..5341f671 100755
--- a/doc/apibuild.py
+++ b/doc/apibuild.py
@@ -80,7 +80,6 @@ ignored_words = {
   "ATTRIBUTE_PRINTF": (5, "macro for gcc printf args checking extension"),
   "LIBXML_ATTR_FORMAT": (5, "macro for gcc printf args checking extension"),
   "LIBXML_ATTR_ALLOC_SIZE": (3, "macro for gcc checking extension"),
-  "__XML_EXTERNC": (0, "Special macro added for os400"),
 }
 
 def escape(raw):
diff --git a/include/libxml/dict.h b/include/libxml/dict.h
index b83db59a..cf54af1f 100644
--- a/include/libxml/dict.h
+++ b/include/libxml/dict.h
@@ -11,25 +11,18 @@
 #ifndef __XML_DICT_H__
 #define __XML_DICT_H__
 
+#include <stddef.h>
+#include <libxml/xmlversion.h>
+
 #ifdef __cplusplus
-#define __XML_EXTERNC  extern "C"
-#else
-#define __XML_EXTERNC
+extern "C" {
 #endif
 
 /*
  * The dictionary.
  */
-__XML_EXTERNC typedef struct _xmlDict xmlDict;
-__XML_EXTERNC typedef xmlDict *xmlDictPtr;
-
-#include <limits.h>
-#include <libxml/xmlversion.h>
-#include <libxml/tree.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
+typedef struct _xmlDict xmlDict;
+typedef xmlDict *xmlDictPtr;
 
 /*
  * Initializer