Fix compile warning from clang
Fix compile warning from clang

Change-Id: If5bfed8fd995f4feeceafe4f6cd618e5a259dd81
Reviewed-on: http://review.couchbase.org/40488
Reviewed-by: Trond Norbye <60edd2ef23891a753f231b0c6f161dc634079a93@gmail.com>
Tested-by: Trond Norbye <60edd2ef23891a753f231b0c6f161dc634079a93@gmail.com>

mrkwse/memcached,cloudrain21/memcached-1,daverigby/memcached,daverigby/memcached,mrkwse/memcached,daverigby/memcached,cloudrain21/memcached-1,owendCB/memcached,owendCB/memcached,jimwwalker/memcached,owendCB/memcached,daverigby/kv_engine,owendCB/memcached,daverigby/kv_engine,daverigby/memcached,cloudrain21/memcached-1,cloudrain21/memcached-1,daverigby/kv_engine,couchbase/memcached,jimwwalker/memcached,daverigby/kv_engine,couchbase/memcached,couchbase/memcached,mrkwse/memcached,couchbase/memcached,mrkwse/memcached,jimwwalker/memcached