Remove one of many unused functions in misc module.

Change-Id: Id03929f85aa3ad725b5be25198f0987fd92c8c44
Reviewed-on: http://review.couchbase.org/39226
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>