makeModulesClosure: support firmware

Link it in stage 1.

nixos/modules/system/boot/stage-1-init.sh

@@ -167,6 +167,7 @@ done
 # Load the required kernel modules.
 mkdir -p /lib
 ln -s @modulesClosure@/lib/modules /lib/modules
+ln -s @modulesClosure@/lib/firmware /lib/firmware
 echo @extraUtils@/bin/modprobe > /proc/sys/kernel/modprobe
 for i in @kernelModules@; do
     echo "loading module $(basename $i)..."

nixos/modules/system/boot/stage-1.nix

@@ -13,12 +13,14 @@ let
 
   kernelPackages = config.boot.kernelPackages;
   modulesTree = config.system.modulesTree;
+  firmware = config.hardware.firmware;
 
 
   # Determine the set of modules that we need to mount the root FS.
   modulesClosure = pkgs.makeModulesClosure {
     rootModules = config.boot.initrd.availableKernelModules ++ config.boot.initrd.kernelModules;
     kernel = modulesTree;
+    firmware = firmware;
     allowMissing = true;
   };