[libxml2] Fix memory leak in xmlCanonicPath

[Nick Wellnhofer <nwellnhof src gnome org>]

commit d6b3645f9b72e55fece09c8d49f91e78a812b0f4
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Sat May 27 14:44:36 2017 +0200

    Fix memory leak in xmlCanonicPath
    
    Found with libFuzzer and ASan.

 uri.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/uri.c b/uri.c
index 2bd5720..530ce21 100644
--- a/uri.c
+++ b/uri.c
@@ -2455,6 +2455,7 @@ xmlCanonicPath(const xmlChar *path)
                xmlFreeURI(uri);
                return escURI;
            }
+            xmlFree(escURI);
        }
     }