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/doc/manual/preface.xml

@@ -0,0 +1,42 @@
+<preface xmlns="http://docbook.org/ns/docbook"
+         xmlns:xlink="http://www.w3.org/1999/xlink"
+         xml:id="preface">
+ <title>Preface</title>
+ <para>
+  This manual describes how to install, use and extend NixOS, a Linux
+  distribution based on the purely functional package management system
+  <link xlink:href="https://nixos.org/nix">Nix</link>, that is composed
+  using modules and packages defined in the
+  <link xlink:href="https://nixos.org/nixpkgs">Nixpkgs</link> project.
+ </para>
+ <para>
+  Additional information regarding the Nix package manager and the Nixpkgs
+  project can be found in respectively the
+  <link xlink:href="https://nixos.org/nix/manual">Nix manual</link> and the
+  <link xlink:href="https://nixos.org/nixpkgs/manual">Nixpkgs manual</link>.
+ </para>
+ <para>
+  If you encounter problems, please report them on the
+  <literal
+   xlink:href="https://discourse.nixos.org">Discourse</literal>,
+  the <link
+   xlink:href="https://matrix.to/#nix:nixos.org">Matrix room</link>,
+  or on the <link
+   xlink:href="irc://irc.libera.chat/#nixos">
+  <literal>#nixos</literal> channel on Libera.Chat</link>.
+  Alternatively, consider <link
+   xlink:href="#chap-contributing">
+   contributing to this manual</link>. Bugs should be
+  reported in
+  <link
+   xlink:href="https://github.com/NixOS/nixpkgs/issues">NixOS’
+  GitHub issue tracker</link>.
+ </para>
+ <note>
+  <para>
+   Commands prefixed with <literal>#</literal> have to be run as root, either
+   requiring to login as root user or temporarily switching to it using
+   <literal>sudo</literal> for example.
+  </para>
+ </note>
+</preface>