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/applications/misc/ptask/json_c_is_error.patch

@@ -0,0 +1,13 @@
+diff --git a/src/tw.c b/src/tw.c
+index 602f7b3..ca601cd 100644
+--- a/src/tw.c
++++ b/src/tw.c
+@@ -163,7 +163,7 @@ static struct json_object *task_exec_json(const char *opts)
+ 
+ 	free(cmd);
+ 
+-	if (o && is_error(o))
++	if (!o)
+ 		return NULL;
+ 
+ 	return o;