[xml] typo in valid.c

[Christian Glahn <christian glahn uibk ac at>]

hallo Daniel,
hallo all,

While debugging because of a segmentation fault I found a minor typo 
in valid.c. Although it's not a bug, but I think it's worth to be 
corrected :)

--- valid.c          
+++ valid.c.typo    
@@ -4837,7 +4837,7 @@
     int ret = 1;
     xmlNodePtr cur, child;
 
-    if ((ctxt == NULL) || (doc == NULL) | (elem == NULL))
+    if ((ctxt == NULL) || (doc == NULL) || (elem == NULL))
        return(0);
 
     child = elem->children;

Christian