filelog.cmp: return 0 for equality

spotted by Alexis Carvalho

mercurial/filelog.py

@@ -71,7 +71,7 b' class filelog(revlog):'
         # for renames, we have to go the slow way
         if self.renamed(node):
             t2 = self.read(node)
-            return t2 == text
+            return t2 != text
 
         return revlog.cmp(self, node, text)