Bug-8053 OVS Bridge other_config:hwaddr not preserved for nodes not in config DS

Bug-8053 OVS Bridge other_config:hwaddr not preserved for nodes not in config DS

1) Make sure to retain operational DS other_configs for existing bridges
2) Set other_config:datapath-id for all bridges already in operational. This
is important to guarantee dpid does not change even for bridges where the
other_config:hwaddr or other_config:datapath_id vals are not set.

DEPENDS ON: https://git.opendaylight.org/gerrit/53856

Change-Id: I5aa792262230655bf753045290666c73aaa4096b
Signed-off-by: Josh <jhershbe@redhat.com>