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/misc/exa/update-cargo-lock.diff

@@ -0,0 +1,13 @@
+diff --git a/Cargo.lock b/Cargo.lock
+index df94188..ed3a068 100644
+--- a/Cargo.lock
++++ b/Cargo.lock
+@@ -57,7 +57,7 @@ dependencies = [
+ 
+ [[package]]
+ name = "exa"
+-version = "0.11.0-pre"
++version = "0.10.1"
+ dependencies = [
+  "ansi_term",
+  "datetime",