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>

pkgs/os-specific/linux/sdnotify-wrapper/default.nix

@@ -0,0 +1,38 @@
+{ stdenv, lib, runCommandCC, skawarePackages }:
+
+with skawarePackages;
+
+let
+  # From https://skarnet.org/software/misc/sdnotify-wrapper.c,
+  # which is unversioned.
+  src = ./sdnotify-wrapper.c;
+
+in runCommandCC "sdnotify-wrapper" {
+
+   outputs = [ "bin" "doc" "out" ];
+
+   meta = {
+     broken = stdenv.isDarwin;
+     homepage = "https://skarnet.org/software/misc/sdnotify-wrapper.c";
+     description = "Use systemd sd_notify without having to link against libsystemd";
+     platforms = lib.platforms.all;
+     license = lib.licenses.isc;
+     maintainers = with lib.maintainers; [ Profpatsch ];
+   };
+
+} ''
+  mkdir -p $bin/bin
+  mkdir $out
+
+  # the -lskarnet has to come at the end to support static builds
+  $CC \
+    -o $bin/bin/sdnotify-wrapper \
+    -I${skalibs.dev}/include \
+    -L${skalibs.lib}/lib \
+    ${src} \
+    -lskarnet
+
+  mkdir -p $doc/share/doc/sdnotify-wrapper
+  # copy the documentation comment
+  sed -ne '/Usage:/,/*\//p' ${src} > $doc/share/doc/sdnotify-wrapper/README
+''