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/tools/misc/coreboot-toolchain/update.sh

@@ -0,0 +1,36 @@
+#!/usr/bin/env nix-shell
+#!nix-shell --pure -i bash -p nix cacert git getopt
+
+if [ ! -d .git ]; then
+  echo "This script needs to be run from the root directory of nixpkgs. Exiting."
+  exit 1
+fi
+
+pkg_dir="$(dirname "$0")"
+
+src="$(nix-build . --no-out-link -A coreboot-toolchain.i386.src)"
+urls=$($src/util/crossgcc/buildgcc -u)
+
+tmp=$(mktemp)
+echo '{ fetchurl }: [' > $tmp
+
+for url in $urls; do
+  name="$(basename $url)"
+  hash="$(nix-prefetch-url "$url")"
+
+  cat << EOF >> $tmp
+  {
+    name = "$name";
+    archive = fetchurl {
+      sha256 = "$hash";
+      url = "$url";
+    };
+  }
+EOF
+done
+
+echo ']' >> $tmp
+
+sed -ie 's/https\:\/\/ftpmirror\.gnu\.org/mirror\:\/\/gnu/g' $tmp
+
+mv $tmp $pkg_dir/sources.nix