log unexpected remote_clusters_info errors

Change-Id: Ic89db558b853c2c69d5464245dfa65c9b953599b
Reviewed-on: http://review.couchbase.org/32373
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>