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/electron/print-hashes.sh

@@ -0,0 +1,39 @@
+#!/usr/bin/env bash
+
+set -eu -o pipefail
+
+if [[ $# -lt 1 ]]; then
+    echo "$0: version" >&2
+    exit 1
+fi
+
+
+VERSION=$1
+
+declare -A SYSTEMS HASHES
+SYSTEMS=(
+    [i686-linux]=linux-ia32
+    [x86_64-linux]=linux-x64
+    [armv7l-linux]=linux-armv7l
+    [aarch64-linux]=linux-arm64
+    [x86_64-darwin]=darwin-x64
+    [aarch64-darwin]=darwin-arm64
+)
+
+hashfile="$(nix-prefetch-url --print-path "https://github.com/electron/electron/releases/download/v${VERSION}/SHASUMS256.txt" 2>/dev/null | tail -n1)"
+headers="$(nix-prefetch-url "https://atom.io/download/electron/v${VERSION}/node-v${VERSION}-headers.tar.gz")"
+
+# Entry similar to the following goes in default.nix:
+
+echo "  electron_${VERSION%%.*} = mkElectron \"${VERSION}\" {"
+
+for S in "${!SYSTEMS[@]}"; do
+  hash="$(grep " *electron-v${VERSION}-${SYSTEMS[$S]}.zip$" "$hashfile"|cut -f1 -d' ' || :)"
+  if [[ -n $hash ]]; then
+    echo "    $S = \"$hash\";"
+  fi
+done
+
+echo "    headers = \"$headers\";"
+
+echo "  };"