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>

nixos/tests/common/acme/server/generate-certs.nix

@@ -0,0 +1,29 @@
+# Minica can provide a CA key and cert, plus a key
+# and cert for our fake CA server's Web Front End (WFE).
+{
+  pkgs ? import <nixpkgs> {},
+  minica ? pkgs.minica,
+  mkDerivation ? pkgs.stdenv.mkDerivation
+}:
+let
+  conf = import ./snakeoil-certs.nix;
+  domain = conf.domain;
+in mkDerivation {
+  name = "test-certs";
+  buildInputs = [ minica ];
+  phases = [ "buildPhase" "installPhase" ];
+
+  buildPhase = ''
+    minica \
+      --ca-key ca.key.pem \
+      --ca-cert ca.cert.pem \
+      --domains ${domain}
+  '';
+
+  installPhase = ''
+    mkdir -p $out
+    mv ca.*.pem $out/
+    mv ${domain}/key.pem $out/${domain}.key.pem
+    mv ${domain}/cert.pem $out/${domain}.cert.pem
+  '';
+}