avoid bogus file not found warning on broken symlink

Not sure why this didn't happen all the time, but the fix is clearly
correct and also saves one stat per file.

Seek.hs

@@ -28,7 +28,7 @@ seekHelper a params = do
 		runSegmentPaths (\fs -> Git.Command.leaveZombie <$> a fs g) params
 	{- Show warnings only for files/directories that do not exist. -}
 	forM_ (map fst $ filter (null . snd) $ zip params ll) $ \p ->
-		unlessM (liftIO $ doesFileExist p <||> doesDirectoryExist p) $
+		unlessM (isJust <$> (liftIO $ catchMaybeIO $ getSymbolicLinkStatus p)) $
 			fileNotFound p
 	return $ concat ll