util: use existing never() instead of custom lambda

mercurial/util.py

@@ -607,7 +607,7 b" def matcher(canonroot, cwd='', names=[],"
     if inc:
         dummy, inckinds, dummy = normalizepats(inc, 'glob')
         incmatch = matchfn(inckinds, '(?:/|$)')
-    excmatch = lambda fn: False
+    excmatch = never
     if exc:
         dummy, exckinds, dummy = normalizepats(exc, 'glob')
         excmatch = matchfn(exckinds, '(?:/|$)')