re-enable kernel checkedConfig support

Sometimes config options get silenty removed because they have
dependencies on other options that haven't been enabled. If you add
those as attributes here, the kernel build will check they're _still_
present in the config after make oldconfig has run.

default.nix

@@ -14,7 +14,7 @@ let
   ] nixpkgs.pkgs;
   squashfs = liminix.builders.squashfs config.filesystem.contents;
   kernel = callPackage ./kernel {
-    inherit (config.kernel) config;
+    inherit (config.kernel) config checkedConfig;
   };
 in {
   outputs = {

kernel/default.nix

@@ -5,6 +5,7 @@
 , fetchFromGitHub
 
 , config
+, checkedConfig
 }:
 let
   source = fetchFromGitHub {
@@ -36,7 +37,6 @@ let
 in
 {
   vmlinux = callPackage ./vmlinux.nix {
-    inherit tree;
-    inherit config;
+    inherit tree config checkedConfig;
   };
 }