monitor: Reorder intialization to drop initial mux focus

monitor: Reorder intialization to drop initial mux focus

So far a multiplexed monitor started disabled. Restore this property for
the new way of configuring by moving the monitor initialization before
all devices (the last one to attach to a char-mux will gain the focus).

Once we have a real use case for that, we may also consider assigning
the initial focus explicitly.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>