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>

doc/builders/images/ocitools.section.md

@@ -0,0 +1,37 @@
+# pkgs.ociTools {#sec-pkgs-ociTools}
+
+`pkgs.ociTools` is a set of functions for creating containers according to the [OCI container specification v1.0.0](https://github.com/opencontainers/runtime-spec). Beyond that, it makes no assumptions about the container runner you choose to use to run the created container.
+
+## buildContainer {#ssec-pkgs-ociTools-buildContainer}
+
+This function creates a simple OCI container that runs a single command inside of it. An OCI container consists of a `config.json` and a rootfs directory. The nix store of the container will contain all referenced dependencies of the given command.
+
+The parameters of `buildContainer` with an example value are described below:
+
+```nix
+buildContainer {
+  args = [
+    (with pkgs;
+      writeScript "run.sh" ''
+        #!${bash}/bin/bash
+        exec ${bash}/bin/bash
+      '').outPath
+  ];
+
+  mounts = {
+    "/data" = {
+      type = "none";
+      source = "/var/lib/mydata";
+      options = [ "bind" ];
+    };
+  };
+
+  readonly = false;
+}
+```
+
+- `args` specifies a set of arguments to run inside the container. This is the only required argument for `buildContainer`. All referenced packages inside the derivation will be made available inside the container.
+
+- `mounts` specifies additional mount points chosen by the user. By default only a minimal set of necessary filesystems are mounted into the container (e.g procfs, cgroupfs)
+
+- `readonly` makes the container\'s rootfs read-only if it is set to true. The default value is false `false`.