Fix XML empty element handling

Change-Id: I80a1653685e221731f9be889b2794f3bc6a38cf2
diff --git a/src/tokenizer.xfst b/src/tokenizer.xfst
index 0d703a3..7b16fb8 100644
--- a/src/tokenizer.xfst
+++ b/src/tokenizer.xfst
@@ -147,6 +147,7 @@
             [[%" [? - %" - %>]+ %"] | [%' [? - %' - %>]+ %']]
           )
         ]*
+        (WS* "/")   
       ]
       |
       [