Revert "hspellDicts.*: remove invalid buildFlags meta attr"

This reverts commit 7084c052a0.

pkgs/development/libraries/hspell/dicts.nix

@@ -6,6 +6,9 @@ let
     meta = hspell.meta // {
       broken = true;
       description = "${variant} Hebrew dictionary";
+
+      buildFlags = [ variant ];
+
     } // (if a ? meta then a.meta else {});
   } // (removeAttrs a ["meta"]));
 in