[libxml2] Fix library problems with mingw-w64

[Daniel Veillard <veillard src gnome org>]

commit 1eabc31401b7b8c3b5273993778f37eeef37a055
Author: Michael Cronenworth <mike cchtml com>
Date:   Thu May 10 11:25:38 2012 +0800

    Fix library problems with mingw-w64
    
    For https://bugzilla.gnome.org/show_bug.cgi?id=663588
    Fix a windows only issue when compiling the library with
    MingW (64 bits) using Fedora cross-compiler chain.
    Change the dllexport for data

 include/libxml/xmlexports.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/include/libxml/xmlexports.h b/include/libxml/xmlexports.h
index 9c6790c..c6516b4 100644
--- a/include/libxml/xmlexports.h
+++ b/include/libxml/xmlexports.h
@@ -115,7 +115,7 @@
    */
   #if defined(IN_LIBXML) && !defined(LIBXML_STATIC)
     #define XMLPUBFUN __declspec(dllexport)
-    #define XMLPUBVAR __declspec(dllexport)
+    #define XMLPUBVAR __declspec(dllexport) extern
   #else
     #define XMLPUBFUN
     #if !defined(LIBXML_STATIC)