osd: Revert use of dmclock message feature bit since not yet finalized

osd: Revert use of dmclock message feature bit since not yet finalized

Because the updated use of dmclock is not yet finalized and the
unfinished functionality uses a valuable messaging feature bit that we
don't want to waste, we're removing it for the mimic release and from
master.

Reverts most of the following commits for mimic:

  de8110ebb39401d3e09cb871f843776421ccd56f
  739d7e462f3a03c4e188fcfa48eb05c0063970c9
  2361e9c790306e789393323ef349d8b4a20bc70d
  9b702cf8fc2ff881ca16edc78874f2118a2e4641

Signed-off-by: J. Eric Ivancich <ivancich@redhat.com>