Revert "Fix for ghc 9.0"

This reverts commit 2882a97.

Author: jhrcek

src/HieDb/Compat.hs

@@ -1,6 +1,5 @@
 
 {-# LANGUAGE CPP, PatternSynonyms, ViewPatterns, TupleSections #-}
-{-# OPTIONS_GHC -Wno-orphans #-} -- ghc 9.0 doesn't have Show instance for ModuleName
 module HieDb.Compat (
     nodeInfo'
     , Unit
@@ -217,8 +216,3 @@ fieldNameSpace_maybe _ = Nothing
 fieldName :: FastString -> NameSpace
 fieldName _ = varName
 #endif
-
-#if __GLASGOW_HASKELL__ < 902
-instance Show ModuleName where
-    show = moduleNameString
-#endif

test/Test/Orphans.hs

@@ -1,10 +1,13 @@
-{-# LANGUAGE StandaloneDeriving #-}
-{-# OPTIONS_GHC -Wno-orphans #-}
+{-# LANGUAGE StandaloneDeriving, CPP #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
 module Test.Orphans where
 
 import HieDb.Compat
 import HieDb.Types
 
+#if __GLASGOW_HASKELL__ < 902
+instance Show ModuleName where show = moduleNameString
+#endif
 instance Show OccName where show = occNameString
 instance Show Name where
   show n =