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/build-support/rust/sysroot/update-lockfile.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i bash -p python3 python3.pkgs.toml cargo
+
+set -eu pipefile
+
+HERE=$(readlink -e $(dirname "${BASH_SOURCE[0]}"))
+NIXPKGS_ROOT="$HERE/../../../.."
+
+# https://unix.stackexchange.com/a/84980/390173
+tempdir=$(mktemp -d 2>/dev/null || mktemp -d -t 'update-lockfile')
+cd "$tempdir"
+mkdir -p src
+touch src/lib.rs
+
+RUSTC_SRC=$(nix-build "${NIXPKGS_ROOT}" -A pkgs.rustPlatform.rustLibSrc --no-out-link)
+
+ln -s $RUSTC_SRC/{core,alloc} ./
+
+export RUSTC_SRC
+python3 "$HERE/cargo.py"
+
+export RUSTC_BOOTSTRAP=1
+cargo generate-lockfile
+
+cp Cargo.lock "$HERE"
+
+rm -rf "$tempdir"