uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

nixos/tests/loki.nix

@@ -0,0 +1,56 @@
+import ./make-test-python.nix ({ lib, pkgs, ... }:
+
+{
+  name = "loki";
+
+  meta = with lib.maintainers; {
+    maintainers = [ willibutz ];
+  };
+
+  nodes.machine = { ... }: {
+    services.loki = {
+      enable = true;
+      configFile = "${pkgs.grafana-loki.src}/cmd/loki/loki-local-config.yaml";
+    };
+    services.promtail = {
+      enable = true;
+      configuration = {
+        server = {
+          http_listen_port = 9080;
+          grpc_listen_port = 0;
+        };
+        clients = [ { url = "http://localhost:3100/loki/api/v1/push"; } ];
+        scrape_configs = [
+          {
+            job_name = "system";
+            static_configs = [
+              {
+                targets = [ "localhost" ];
+                labels = {
+                  job = "varlogs";
+                  __path__ = "/var/log/*log";
+                };
+              }
+            ];
+          }
+        ];
+      };
+    };
+  };
+
+  testScript = ''
+    machine.start
+    machine.wait_for_unit("loki.service")
+    machine.wait_for_unit("promtail.service")
+    machine.wait_for_open_port(3100)
+    machine.wait_for_open_port(9080)
+    machine.succeed("echo 'Loki Ingestion Test' > /var/log/testlog")
+    # should not have access to journal unless specified
+    machine.fail(
+        "systemctl show --property=SupplementaryGroups promtail | grep -q systemd-journal"
+    )
+    machine.wait_until_succeeds(
+        "${pkgs.grafana-loki}/bin/logcli --addr='http://localhost:3100' query --no-labels '{job=\"varlogs\",filename=\"/var/log/testlog\"}' | grep -q 'Loki Ingestion Test'"
+    )
+  '';
+})