revert parentDir change

Reverts 965e106f24

Unfortunately, this caused breakage on Windows, and possibly elsewhere,
because parentDir and takeDirectory do not behave the same when there is a
trailing directory separator.

Logs/FsckResults.hs

@@ -29,7 +29,7 @@ writeFsckResults u fsckresults = do
 				| otherwise -> store s t logfile
   where
 	store s t logfile = do 
-		createDirectoryIfMissing True (takeDirectory logfile)
+		createDirectoryIfMissing True (parentDir logfile)
 		liftIO $ viaTmp writeFile logfile $ serialize s t
 	serialize s t =
 		let ls = map fromRef (S.toList s)