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/release/functions.sh

@@ -0,0 +1,17 @@
+findTarball() {
+    local suffix i
+    if [ -d "$1/tarballs/" ]; then
+        for suffix in tar.gz tgz tar.bz2 tbz2 tbz tar.xz txz tar.lzma; do
+            for i in $1/tarballs/*.$suffix; do echo $i; break; done
+        done | sort | head -1
+        return
+    else
+        echo "$1"
+        return
+    fi
+}
+
+propagateImageName() {
+    mkdir -p $out/nix-support
+    cat "$diskImage"/nix-support/full-name > $out/nix-support/full-name
+}