ceph-disk: don't activate suppressed journal devices

ceph-disk: don't activate suppressed journal devices

Multipath device activation currently requires that devices representing
individual paths making up a multipath device are suppressed, to avoid
errors such as:
  ceph_disk.main.Error: Error: /dev/sda1 is not a multipath block device

Activation of suppressed OSD devices is currently handled by checks in
main_activate() and main_activate_space(). However, suppressed journal
and block devices are not detected.

(Along with udev change) Fixes: http://tracker.ceph.com/issues/19489

Signed-off-by: David Disseldorp <ddiss@suse.de>