Fix console output showing during reboot or shutdown

Messages like "could not parse /path/to/mountinfo" and "watchdog did not
stop" briefly flash on screen during reboot/shutdown.

Another contributing factor is the broadcast (Wall) message "system is
going down NOW".

mkosi.extra/etc/systemd/logind.conf.d/disable-wall.conf

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
+# SPDX-FileCopyrightText: 2026 Vishal Rao <vishalrao@gmail.com>
+
+[Login]
+WallMessages=no

mkosi.extra/usr/lib/initcpio/install/sd-shutdown

@@ -0,0 +1,9 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
+# SPDX-FileCopyrightText: 2025-2026 Vishal Rao <vishalrao@gmail.com>
+
+build() {
+    map add_binary \
+        /usr/lib/libblkid.so \
+        /usr/lib/libmount.so
+}

mkosi.extra/usr/lib/rebuild-efi

@@ -30,7 +30,7 @@ cat <<- EOF > mkinitcpio.conf
 MODULES=(overlay)
 BINARIES=()
 FILES=()
-HOOKS=(base systemd modconf kms keyboard block sd-encrypt filesystems fsck systemd-extension plymouth microcode)
+HOOKS=(base systemd modconf kms keyboard block sd-encrypt filesystems fsck systemd-extension plymouth microcode sd-shutdown)
 EOF
 
 echo "rw \