unbundle: fix pyflakes warning about wc

mercurial/commands.py

@@ -5869,7 +5869,6 b' def unbundle(ui, repo, fname1, *fnames, '
     fnames = (fname1,) + fnames
 
     lock = repo.lock()
-    wc = repo['.']
     try:
         for fname in fnames:
             f = hg.openpath(ui, fname)