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/tools/archivers/unrar/default.nix

@@ -0,0 +1,54 @@
+{lib, stdenv, fetchurl}:
+
+stdenv.mkDerivation rec {
+  pname = "unrar";
+  version = "6.1.6";
+
+  src = fetchurl {
+    url = "https://www.rarlab.com/rar/unrarsrc-${version}.tar.gz";
+    sha256 = "sha256-Z/SriRwGIhjCut+qycjKtci/1eltq/ylbI+qPSCagB0=";
+  };
+
+  postPatch = ''
+    substituteInPlace makefile \
+      --replace "CXX=" "#CXX=" \
+      --replace "STRIP=" "#STRIP=" \
+      --replace "AR=" "#AR="
+  '';
+
+  buildPhase = ''
+    # `make {unrar,lib}` call `make clean` implicitly
+    # move build results to another dir to avoid deleting them
+    mkdir -p bin
+
+    make unrar
+    mv unrar bin
+
+    make lib
+    mv libunrar.so bin
+  '';
+
+  outputs = [ "out" "dev" ];
+
+  installPhase = ''
+    install -Dt "$out/bin" bin/unrar
+
+    mkdir -p $out/share/doc/unrar
+    cp acknow.txt license.txt \
+        $out/share/doc/unrar
+
+    install -Dm755 bin/libunrar.so $out/lib/libunrar.so
+
+    install -Dt $dev/include/unrar/ *.hpp
+  '';
+
+  setupHook = ./setup-hook.sh;
+
+  meta = with lib; {
+    description = "Utility for RAR archives";
+    homepage = "https://www.rarlab.com/";
+    license = licenses.unfreeRedistributable;
+    maintainers = [ maintainers.ehmry ];
+    platforms = platforms.all;
+  };
+}