Move responsibility for disabling upstream tahoe.

nixos/modules/private-storage.nix

@@ -21,14 +21,6 @@ let
   max-incident-age = "29d";
 in
 {
-  # Upstream tahoe-lafs module conflicts with ours (since ours is a
-  # copy/paste/edit of upstream's...).  Disable it.
-  #
-  # https://nixos.org/nixos/manual/#sec-replace-modules
-  disabledModules =
-  [ "services/network-filesystems/tahoe.nix"
-  ];
-
   imports = [
     # Give it a good SSH configuration.
     ./ssh.nix

nixos/modules/tahoe.nix

@@ -9,6 +9,14 @@ let
   ini = pkgs.callPackage ../lib/ini.nix { };
 in
   {
+    # Upstream tahoe-lafs module conflicts with ours (since ours is a
+    # copy/paste/edit of upstream's...).  Disable it.
+    #
+    # https://nixos.org/nixos/manual/#sec-replace-modules
+    disabledModules =
+    [ "services/network-filesystems/tahoe.nix"
+    ];
+
     options.services.tahoe = {
       introducers = mkOption {
         default = {};