fixed to skip (if necessary) the BOM for encoding 'utf-16'. Completes the

* parserInternals.c: fixed to skip (if necessary) the BOM for
  encoding 'utf-16'.  Completes the fix for bug #152286.
* tree.c, parser.c: minor warning cleanup, no change to logic
diff --git a/tree.c b/tree.c
index 134ce20..805db66 100644
--- a/tree.c
+++ b/tree.c
@@ -37,6 +37,9 @@
 #ifdef LIBXML_HTML_ENABLED
 #include <libxml/HTMLtree.h>
 #endif
+#ifdef LIBXML_DEBUG_ENABLED
+#include <libxml/debugXML.h>
+#endif
 
 int __xmlRegisterCallbacks = 0;