vdev_id: fix failure due to multipath -l bug

vdev_id: fix failure due to multipath -l bug

Udev may fail to create the expected symbolic links in
/dev/disk/by-vdev on systems with the
device-mapper-multipath-0.4.9-100.el6 package installed. This affects
RHEL 6.9 and possibly other downstream distributions.

That version of the multipath command may incorrectly list a drive
state as "unkown" instead of "running". The issue was introduced
in the patch for https://bugzilla.redhat.com/show_bug.cgi?id=1401769

The vdev_id udev helper uses the state reported by "multipath -l" to
detect an online component disk of a multipath device in order to
resolve its physical slot and enclosure. Changing the command
invocation to "multipath -ll" works around the above issue by causing
multipath to consult additional sources of information to determine
the drive state.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes #6039