[libxml2] Correct a typo.

[Daniel Veillard <veillard src gnome org>]

commit d5bd2a9a4064e1d0da6367bb0ee4de7d337964bf
Author: Shlomi Fish <shlomif shlomifish org>
Date:   Sun Apr 3 05:14:44 2016 +0300

    Correct a typo.

 xpath.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/xpath.c b/xpath.c
index 935fcff..512bbf4 100644
--- a/xpath.c
+++ b/xpath.c
@@ -3706,7 +3706,7 @@ xmlXPathNodeSetAdd(xmlNodeSetPtr cur, xmlNodePtr val) {
 
     /* @@ with_ns to check whether namespace nodes should be looked at @@ */
     /*
-     * prevent duplcates
+     * prevent duplicates
      */
     for (i = 0;i < cur->nodeNr;i++)
         if (cur->nodeTab[i] == val) return(0);