etc: mask zfs-load-key.service

Otherwise, systemd-sysv-generator will generate a service equivalent
that breaks the boot: under systemd this is covered by
zfs-mount-generator

We already do this for zfs-import.service, and other init scripts are
suppressed automatically by the "actual" .service files

Fixes: commit f04b976 ("Add init script
 to load keys")
Reviewed-by: George Melikov <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Ahelenia Ziemiańska <[email protected]>
Closes #14010
Closes #14019

Author: nabijaczleweli

etc/systemd/system/Makefile.am

@@ -22,3 +22,4 @@ SUBSTFILES += $(systemdpreset_DATA) $(systemdunit_DATA)
 install-data-hook:
 	$(MKDIR_P) "$(DESTDIR)$(systemdunitdir)"
 	ln -sf /dev/null "$(DESTDIR)$(systemdunitdir)/zfs-import.service"
+	ln -sf /dev/null "$(DESTDIR)$(systemdunitdir)/zfs-load-key.service"