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/drbd.nix

@@ -0,0 +1,87 @@
+import ./make-test-python.nix (
+  { pkgs, lib, ... }:
+  let
+    drbdPort = 7789;
+
+    drbdConfig =
+      { nodes, ... }:
+      {
+        virtualisation.emptyDiskImages = [ 1 ];
+        networking.firewall.allowedTCPPorts = [ drbdPort ];
+
+        services.drbd = {
+          enable = true;
+          config = ''
+            global {
+              usage-count yes;
+            }
+
+            common {
+              net {
+                protocol C;
+                ping-int 1;
+              }
+            }
+
+            resource r0 {
+              volume 0 {
+                device    /dev/drbd0;
+                disk      /dev/vdb;
+                meta-disk internal;
+              }
+
+              on drbd1 {
+                address ${nodes.drbd1.config.networking.primaryIPAddress}:${toString drbdPort};
+              }
+
+              on drbd2 {
+                address ${nodes.drbd2.config.networking.primaryIPAddress}:${toString drbdPort};
+              }
+            }
+          '';
+        };
+      };
+  in
+  {
+    name = "drbd";
+    meta = with pkgs.lib.maintainers; {
+      maintainers = [ ryantm astro ];
+    };
+
+    nodes.drbd1 = drbdConfig;
+    nodes.drbd2 = drbdConfig;
+
+    testScript = { nodes }: ''
+      drbd1.start()
+      drbd2.start()
+
+      drbd1.wait_for_unit("network.target")
+      drbd2.wait_for_unit("network.target")
+
+      drbd1.succeed(
+          "drbdadm create-md r0",
+          "drbdadm up r0",
+          "drbdadm primary r0 --force",
+      )
+
+      drbd2.succeed("drbdadm create-md r0", "drbdadm up r0")
+
+      drbd1.succeed(
+          "mkfs.ext4 /dev/drbd0",
+          "mkdir -p /mnt/drbd",
+          "mount /dev/drbd0 /mnt/drbd",
+          "touch /mnt/drbd/hello",
+          "umount /mnt/drbd",
+          "drbdadm secondary r0",
+      )
+      drbd1.sleep(1)
+
+      drbd2.succeed(
+          "drbdadm primary r0",
+          "mkdir -p /mnt/drbd",
+          "mount /dev/drbd0 /mnt/drbd",
+          "ls /mnt/drbd/hello",
+      )
+    '';
+  }
+)