masked jobs trigger warning about failed dependency

Trivial, as that's already fixed upstream. We'll either get this via 229, or I'll backport it.

This bug was fixed in the package systemd - 228-6ubuntu1

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systemd (228-6ubuntu1) xenial; urgency=medium

  * Merge with Debian unstable. Remaining Ubuntu changes:
    - Hack to support system-image read-only /etc, and modify files in
      /etc/writable/ instead.
    - Build using libseccomp on powerpc and ppc64el (See Debian #800818).

    Upgrade fixes, keep until 16.04 LTS release:
    - systemd Conflicts/Replaces/Provides systemd-services.
    - Remove obsolete systemd-logind upstart job.
    - Clean up obsolete /etc/udev/rules.d/README.
    - systemd.postinst: Migrate mountall specific fstab options to standard
      util-linux "nofail" option.
    - systemctl: Don't forward telinit u to upstart. This works around
      upstart's Restart() always reexec'ing /sbin/init on Restart(), even if
      that changes to point to systemd during the upgrade. This avoids running
      systemd during a dist-upgrade. (LP: #1430479)
    - Provide shutdown fallback for upstart. (LP: #1370329)
    - Break lvm (<< 2.02.133-1ubuntu1) and remove our dummy /etc/init.d/lvm2
      on upgrades, as it's shipped by lvm2 now.
    - Make udev break on mdadm << 3.3-2ubuntu3, as udev's init script dropped
      the "Provides: raid-mdadm".
    - Clean up /var/log/udev on upgrade (which is written under upstart, but
      not under systemd). (LP: #1537211)
    - Migrate existing s390x network configuration to new names. (LP: #1526808)
    - systemd.postinst: Bump Version comparison for migrating the UTC setting
      from /etc/default/rcS to /etc/adjtime, to run it for upgrades to 16.04.

systemd (228-7) UNRELEASED; urgency=medium

  * debian/tests/systemd-fsckd: Tame overly strict test for failed plymouth
    unit, which is a race condition with plymouthd auto-stopping.
    (LP: #1543144)
  * Do not warn about Wants depencencies on masked units. (LP: #1543282)
  * Drop timedated-don-t-rely-on-usr-being-mounted-in-the-ini.patch.
    initramfs-tools has mounted /usr since Jessie, and tzdata now creates
    /etc/localtime as a symlink too (see #803144).
  * Use-different-default-paths-for-various-binaries.patch: Drop path changes
    for setcap (which is already a build dep and not used at all) and sulogin
    (which is now in util-linux).
  * Remove obsolete udev maintainer script checks:
    - Drop check for kernel >= 2.6.32, which released in 2009.
    - Drop restarting of some daemons due to the devtmpfs migration, which
      happened before the above kernel even.
    - Drop support for forcing upgrades on kernels known not to work via
      /etc/udev/kernel-upgrade. Don't pretend that this would help, as users
      could end up with a non-bootable system. Always fail early in preinst
      when it's still possible to install a working kernel.
    - Drop postinst test for "running in containers" -- it's actually possible
      to run udev in containers if you mount /sys r/w and you know what you
      are doing. Also, the init.d script and systemd service do that check
      again.
    - Keep the kernel feature and chroot checks, as these are still useful.
      Simplify check_kernel_features() by eliminating some variables.
    - Drop debconf templ...