mon/MonClient: apply MON config before finishing bootstrap

mon/MonClient: apply MON config before finishing bootstrap

In general, non-primitive config options cannot be updated after
the service threads have been marked as running. In librados, this
happens after the MonClient bootstrap process. However, the configs
received from the MON were applied in a separate thread which can
race with librados marking the service threads as running.

Now the received MON configs will be applied within the context of
the bootstrap function call instead of deferring to a separate
thread.

Signed-off-by: Jason Dillaman <dillaman@redhat.com>