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/common-updater/generic-updater.nix

@@ -0,0 +1,108 @@
+{ stdenv, writeScript, coreutils, gnugrep, gnused, common-updater-scripts, nix }:
+
+{ pname
+, version
+, attrPath ? pname
+, versionLister
+, ignoredVersions ? ""
+, rev-prefix ? ""
+, odd-unstable ? false
+, patchlevel-unstable ? false
+}:
+
+let
+  # where to print git commands and debugging messages
+  fileForGitCommands = "update-git-commits.txt";
+
+  # shell script to update package
+  updateScript = writeScript "update-script.sh" ''
+    #! ${stdenv.shell}
+    set -o errexit
+    set -x
+
+    pname="$1"
+    version="$2"
+    attr_path="$3"
+    version_lister="$4"
+    ignored_versions="$5"
+    rev_prefix="$6"
+    odd_unstable="$7"
+    patchlevel_unstable="$8"
+
+    # print header
+    echo "# $pname-$version" >> ${fileForGitCommands}
+
+    function version_is_ignored() {
+      local tag="$1"
+      [ -n "$ignored_versions" ] && grep -E "$ignored_versions" <<< "$tag"
+    }
+
+    function version_is_unstable() {
+      local tag="$1"
+      local enforce="$2"
+      if [ -n "$odd_unstable" -o -n "$enforce" ]; then
+        local minor=$(echo "$tag" | ${gnused}/bin/sed -rne 's,^[0-9]+\.([0-9]+).*,\1,p')
+        if [ $((minor % 2)) -eq 1 ]; then
+          return 0
+        fi
+      fi
+      if [ -n "$patchlevel_unstable" -o -n "$enforce" ]; then
+        local patchlevel=$(echo "$tag" | ${gnused}/bin/sed -rne 's,^[0-9]+\.[0-9]+\.([0-9]+).*$,\1,p')
+        if ((patchlevel >= 90)); then
+          return 0
+        fi
+      fi
+      return 1
+    }
+
+    tags=$($version_lister --pname=${pname} --file="${fileForGitCommands}") || exit 1
+
+    # print available tags
+    for tag in $tags; do
+        echo "#	found $pname version: $tag" >> ${fileForGitCommands}
+    done
+
+    # cut any revision prefix not used in the NixOS package version
+    if [ -n "$rev_prefix" ]; then
+      tags=$(echo "$tags" | ${gnugrep}/bin/grep "^$rev_prefix")
+      tags=$(echo "$tags" | ${gnused}/bin/sed -e "s,^$rev_prefix,,")
+    fi
+    tags=$(echo "$tags" | ${gnugrep}/bin/grep "^[0-9]")
+
+    # sort the tags in decreasing order
+    tags=$(echo "$tags" | ${coreutils}/bin/sort --reverse --version-sort)
+
+    # find the newest tag
+    # do not consider development versions
+    for latest_tag in $tags; do
+      if version_is_ignored "$latest_tag"; then
+        echo "#   skip ignored version: $pname-$latest_tag" >> ${fileForGitCommands}
+        latest_tag=
+      elif version_is_unstable "$latest_tag"; then
+        echo "#   skip development version: $pname-$latest_tag" >> ${fileForGitCommands}
+        latest_tag=
+      else
+        if version_is_unstable "$latest_tag" "enforce"; then
+          echo "#   use potential development version: $pname-$latest_tag" >> ${fileForGitCommands}
+        fi
+        break
+      fi
+    done
+
+    if [ -n "$latest_tag" ]; then
+      # print commands to commit the changes
+      if [ "$version" != "$latest_tag" ]; then
+        pfile=$(EDITOR=echo ${nix}/bin/nix edit -f. "$attr_path")
+        echo "   git add $pfile " >> ${fileForGitCommands}
+        echo "   git commit -m '$attr_path: $version -> $latest_tag'" >> ${fileForGitCommands}
+      fi
+
+      # update the nix expression
+      ${common-updater-scripts}/bin/update-source-version "$attr_path" "$latest_tag"
+    fi
+
+    echo "" >> ${fileForGitCommands}
+  '';
+
+in
+[ updateScript pname version attrPath versionLister ignoredVersions rev-prefix odd-unstable patchlevel-unstable ]