Activate the "XInclude" feature by default

The XInclude feature allows "xi:include" nodes to be expanded by inserting the
referenced document as described by http://www.w3.org/TR/xinclude.

This patch modifies xmlversion.h, which is a product of the "configure" step
and in the vanilla libxml2's default configuration, XInclude is activated.

Change-Id: I09b7d330336446c2419e2ef272dd7fa736e6c8f2
Signed-off-by: David Wagner <david.wagner@intel.com>
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
Signed-off-by: Jack Ren <jack.ren@intel.com>
Author-Tracking-BZ: 168727

include/libxml/xmlversion.h

@@ -255,7 +255,7 @@ XMLPUBFUN void XMLCALL xmlCheckVersion(int version);
  *
  * Whether XInclude is configured in
  */
-#if 0
+#if 1
 #define LIBXML_XINCLUDE_ENABLED
 #endif