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/tools/system/safecopy/default.nix

@@ -0,0 +1,31 @@
+{ lib, stdenv, fetchurl }:
+
+stdenv.mkDerivation rec {
+  pname = "safecopy";
+  version = "1.7";
+
+  src = fetchurl {
+    url = "mirror://sourceforge/project/safecopy/safecopy/safecopy-${version}/safecopy-${version}.tar.gz";
+    sha256 = "1zf4kk9r8za9pn4hzy1y3j02vrhl1rxfk5adyfq0w0k48xfyvys2";
+  };
+
+  meta = {
+    description = "Data recovery tool for damaged hardware";
+
+    longDescription =
+      '' Safecopy is a data recovery tool which tries to extract as much data as possible from a
+         problematic (i.e. damaged sectors) source - like floppy drives, hard disk partitions, CDs,
+         tape devices, etc, where other tools like dd would fail due to I/O errors.
+
+         Safecopy includes a low level IO layer to read CDROM disks in raw mode, and issue device
+         resets and other helpful low level operations on a number of other device classes.
+       '';
+
+    homepage = "http://safecopy.sourceforge.net";
+
+    license = lib.licenses.gpl2Plus;
+
+    platforms = lib.platforms.linux;
+    maintainers = [ lib.maintainers.bluescreen303 ];
+  };
+}