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.

Upgrade/V5.hs

@@ -32,6 +32,7 @@ import Git.Ref
 import Utility.InodeCache
 import Utility.DottedVersion
 import Annex.AdjustedBranch
+import qualified Utility.RawFilePath as R
 
 import qualified Data.ByteString as S
 
@@ -156,7 +157,7 @@ upgradeDirectWorkTree = do
 		)
 	
 	writepointer f k = liftIO $ do
-		removeWhenExistsWith removeLink f
+		removeWhenExistsWith R.removeLink (toRawFilePath f)
 		S.writeFile f (formatPointer k)
 
 {- Remove all direct mode bookkeeping files. -}