units: drop RefuseManualStart= from a couple of update services

The only update service we really need to guard like this is
systemd-tmpfiles-setup.service since if invoked manually might create
/var/run/nologin and thus blocking the user from login. The other
services are pretty much idempotent and don't suffer by this problem,
hence let's simplify them.

units/systemd-journal-catalog-update.service.in

@@ -12,8 +12,6 @@ DefaultDependencies=no
 Conflicts=shutdown.target
 After=systemd-readahead-collect.service systemd-readahead-replay.service local-fs.target
 Before=sysinit.target shutdown.target systemd-update-done.service
-RefuseManualStart=yes
-RefuseManualStop=yes
 ConditionNeedsUpdate=/etc
 
 [Service]

units/systemd-sysusers.service.in

@@ -12,8 +12,6 @@ DefaultDependencies=no
 Conflicts=shutdown.target
 After=systemd-readahead-collect.service systemd-readahead-replay.service systemd-remount-fs.service
 Before=sysinit.target shutdown.target systemd-update-done.service
-RefuseManualStart=yes
-RefuseManualStop=yes
 ConditionNeedsUpdate=/etc
 
 [Service]

units/systemd-udev-hwdb-update.service.in

@@ -12,8 +12,6 @@ DefaultDependencies=no
 Conflicts=shutdown.target
 After=systemd-readahead-collect.service systemd-readahead-replay.service systemd-remount-fs.service
 Before=sysinit.target shutdown.target systemd-update-done.service
-RefuseManualStart=yes
-RefuseManualStop=yes
 ConditionNeedsUpdate=/etc
 
 [Service]

units/systemd-update-done.service.in

@@ -12,8 +12,6 @@ DefaultDependencies=no
 Conflicts=shutdown.target
 After=systemd-readahead-collect.service systemd-readahead-replay.service local-fs.target
 Before=sysinit.target shutdown.target
-RefuseManualStart=yes
-RefuseManualStop=yes
 ConditionNeedsUpdate=|/etc
 ConditionNeedsUpdate=|/var