use mapAttrs right

`mapAttrs'` takes two args rather than a set, whereas if only the val
changes `mapAttrs (_: v: ...)` should do

deployment/data-model.nix

@@ -135,9 +135,7 @@ in
               # TODO: maybe transpose, and group the resources by type instead
               type = attrsOf (
                 attrTag (
-                  lib.mapAttrs' (name: resource: {
-                    ${name} = mkOption { type = resource.policy; };
-                  }) config.resources
+                  lib.mapAttrs (_name: resource: mkOption { type = submodule resource.policy; }) config.resources
                 )
               );
             };