Quote arguments in FindIcu

Change-Id: Ibd2e51a669c56c966f83c15343d584bf5aef3937
Reviewed-on: http://review.couchbase.org/28943
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>