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/development/compilers/gnatboot/default.nix

@@ -0,0 +1,55 @@
+{ lib, stdenv, fetchurl }:
+
+if stdenv.hostPlatform != stdenv.targetPlatform
+then builtins.throw "gnatboot can't cross-compile"
+else
+
+stdenv.mkDerivation {
+  pname = "gentoo-gnatboot";
+  version = "4.1";
+
+  src = if stdenv.hostPlatform.system == "i686-linux" then
+    fetchurl {
+      url = "mirror://gentoo/distfiles/gnatboot-4.1-i386.tar.bz2";
+      sha256 = "0665zk71598204bf521vw68i5y6ccqarq9fcxsqp7ccgycb4lysr";
+    }
+  else if stdenv.hostPlatform.system == "x86_64-linux" then
+    fetchurl {
+      url = "mirror://gentoo/distfiles/gnatboot-4.1-amd64.tar.bz2";
+      sha256 = "1li4d52lmbnfs6llcshlbqyik2q2q4bvpir0f7n38nagp0h6j0d4";
+    }
+  else
+    throw "Platform not supported";
+
+  dontStrip = 1;
+
+  installPhase = ''
+    mkdir -p $out
+    cp -R * $out
+
+    set +e
+    for a in $out/bin/* ; do
+      patchelf --interpreter $(cat $NIX_CC/nix-support/dynamic-linker) \
+        --set-rpath $(cat $NIX_CC/nix-support/orig-libc)/lib:$(cat $NIX_CC/nix-support/orig-cc)/lib64:$(cat $NIX_CC/nix-support/orig-cc)/lib $a
+    done
+    set -e
+
+    mv $out/bin/gnatgcc_2wrap $out/bin/gnatgcc
+    ln -s $out/bin/gnatgcc $out/bin/gcc
+  '';
+
+  passthru = {
+    langC = true; # TRICK for gcc-wrapper to wrap it
+    langCC = false;
+    langFortran = false;
+    langAda = true;
+  };
+
+  meta = with lib; {
+    homepage = "https://gentoo.org";
+    license = licenses.gpl3Plus;
+    maintainers = [ maintainers.lucus16 ];
+
+    platforms = platforms.linux;
+  };
+}