Add emergency shutdown feature, triggered by root device removal

usr/libexec/security-misc/force-poweroff-on-boot-media-removal

@@ -0,0 +1,24 @@
+#!/bin/bash
+
+# Copyright (C) 2025 - 2025 ENCRYPTED SUPPORT LLC <adrelanos@whonix.org>
+# See the file COPYING for copying conditions.
+
+gcc \
+  -o \
+  /run/force-shutdown-when-device-removed \
+  -static \
+  /usr/src/security-misc/force-shutdown-when-device-removed.c \
+  || {
+    printf "%s\n" 'Could not compile force-shutdown executable!'
+    exit 1;
+  }
+
+readarray -t root_devices < <(/usr/libexec/helper-scripts/get-backing-devices-for-mountpoint '/');
+
+## memlockd daemonizes itself, so no need to background it
+memlockd -c /usr/share/security-misc/security-misc-memlockd.cfg
+
+/run/force-shutdown-when-device-removed "${root_devices}" &
+sleep 1
+disown
+exit 0