nixos/podman: Create real docker socket instead of symlink

This ensures that both sockets are available after sockets.target.
See hercules-ci/arion#238

nixos/modules/virtualisation/podman/default.nix

@@ -219,6 +219,11 @@ in
       systemd.services.podman.environment = config.networking.proxy.envVars;
       systemd.sockets.podman.wantedBy = [ "sockets.target" ];
       systemd.sockets.podman.socketConfig.SocketGroup = "podman";
+      systemd.sockets.podman.socketConfig.ListenStream = [
+        "/run/podman/podman.sock"
+      ] ++ lib.optional cfg.dockerSocket.enable [
+        "/run/docker.sock"
+      ];
 
       systemd.user.services.podman.environment = config.networking.proxy.envVars;
       systemd.user.sockets.podman.wantedBy = [ "sockets.target" ];
@@ -239,11 +244,6 @@ in
         '')
       ];
 
-      systemd.tmpfiles.rules =
-        lib.optionals cfg.dockerSocket.enable [
-          "L! /run/docker.sock - - - - /run/podman/podman.sock"
-        ];
-
       users.groups.podman = { };
 
       assertions = [