fixed a couple of problems in the new elfgcchack.h trick pointed by Peter

* libxml.h uri.c: fixed a couple of problems in the new
  elfgcchack.h trick pointed by Peter Breitenlohner
Daniel
diff --git a/libxml.h b/libxml.h
index a524f06..e997462 100644
--- a/libxml.h
+++ b/libxml.h
@@ -52,9 +52,11 @@
 
 #ifdef IN_LIBXML
 #ifdef __GNUC__
+#ifdef PIC
 #ifdef linux
 #include "elfgcchack.h"
 #endif
 #endif
 #endif
+#endif
 #endif /* ! __XML_LIBXML_H__ */