kernel: microcode in every initramfs through mkinitcpio's microcode hook (issue 1977)

Declares amd-ucode and intel-ucode, the drop-in /etc/mkinitcpio.conf.d/mesh-microcode.conf, the
initramfs script and mesh-kernel-initramfs.service; kernel_boot answers the running revision and
whether the images were built with the drop-in. Tests: 1977/AC1-AC5.

Builds: L1, L2, L3, L4, L5 (issue 1977 note 2)

modules/kernel/module.json

@@ -119,6 +119,53 @@
       "unit": "linux-modules-cleanup.service",
       "state": "stopped",
       "boot": "enabled"
+    },
+    {
+      "id": "amd-ucode",
+      "type": "package",
+      "package": "amd-ucode"
+    },
+    {
+      "id": "intel-ucode",
+      "type": "package",
+      "package": "intel-ucode"
+    },
+    {
+      "id": "microcode-hook",
+      "type": "file",
+      "path": "/etc/mkinitcpio.conf.d/mesh-microcode.conf",
+      "mode": "0644",
+      "template": "files/mesh-microcode.conf"
+    },
+    {
+      "id": "initramfs",
+      "type": "file",
+      "path": "${dir:state}/initramfs",
+      "mode": "0755",
+      "trusted": true,
+      "template": "files/initramfs.sh"
+    },
+    {
+      "id": "initramfs-unit",
+      "type": "file",
+      "path": "/etc/systemd/system/mesh-kernel-initramfs.service",
+      "mode": "0644",
+      "template": "files/mesh-kernel-initramfs.service"
+    },
+    {
+      "id": "initramfs-apply",
+      "type": "service",
+      "unit": "mesh-kernel-initramfs.service",
+      "state": "running",
+      "boot": "enabled",
+      "restart-on": [
+        "initramfs-unit",
+        "initramfs",
+        "microcode-hook"
+      ],
+      "health": {
+        "kind": "unit"
+      }
     }
   ],
   "build": {