Location: Semigroup deprecated Option in ghc-9.0

It will be removed in 9.2, so just use Maybe

src/Language/Haskell/Exts/Location.hs

@@ -14,11 +14,11 @@ import Language.Haskell.Exts.Syntax
 -- 
 -- The location only indicates the beginning of a range, because that's what
 -- haskell-src-exts provides.
-type Located a = Writer (Option (Min SrcLoc)) a
+type Located a = Writer (Maybe (Min SrcLoc)) a
 
 located :: SrcLoc -> Located ()
-located srcLoc | srcLoc == noLoc = tell $ Option $ Nothing
-               | otherwise       = tell $ Option $ Just $ Min srcLoc
+located srcLoc | srcLoc == noLoc = tell $ Nothing
+               | otherwise       = tell $ Just $ Min srcLoc
 
 annotated :: (Annotated ast, SrcInfo si) => ast si -> Located (ast si)
 annotated x = do
@@ -28,4 +28,4 @@ annotated x = do
 runLocated :: Located a -> (a, Maybe SrcLoc)
 runLocated = go . runWriter
   where
-    go (x, p) = (x, fmap getMin $ getOption $ p)
+    go (x, p) = (x, fmap getMin $ p)