finish fixing removeLink on windows

9cb250f7be got the ones in RawFilePath,
but there were others that used the one from unix-compat, which fails at
runtime on windows. To avoid this,
import System.PosixCompat.Files hiding removeLink

This commit was sponsored by Ethan Aubin.

Annex/Ssh.hs

@@ -337,7 +337,7 @@ forceStopSsh socketfile = withNullHandle $ \nullh -> do
 		}
 	void $ liftIO $ catchMaybeIO $ withCreateProcess p $ \_ _ _ pid ->
 		forceSuccessProcess p pid
-	liftIO $ removeWhenExistsWith removeLink socketfile
+	liftIO $ removeWhenExistsWith R.removeLink (toRawFilePath socketfile)
 
 {- This needs to be as short as possible, due to limitations on the length
  - of the path to a socket file. At the same time, it needs to be unique