Minor refactoring in dcp producer code
Minor refactoring in dcp producer code

String compare complying with C++ standards.

Change-Id: I2ab1ccf08bc1b11da101e819476b6aa466083733
Reviewed-on: http://review.couchbase.org/53811
Reviewed-by: Chiyoung Seo <fcffc23db27b19ee4ebba46695ee6b50e09216a2@couchbase.com>
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

owendCB/ep-engine,owendCB/ep-engine,couchbase/ep-engine,hisundar/ep-engine,daverigby/kv_engine,membase/ep-engine,daverigby/kv_engine,owendCB/ep-engine,teligent-ru/ep-engine,hisundar/ep-engine,couchbase/ep-engine,daverigby/ep-engine,daverigby/kv_engine,couchbase/ep-engine,daverigby/kv_engine,owendCB/ep-engine,membase/ep-engine,daverigby/ep-engine,teligent-ru/ep-engine,membase/ep-engine,daverigby/ep-engine,couchbase/ep-engine,daverigby/ep-engine,teligent-ru/ep-engine,membase/ep-engine,hisundar/ep-engine,hisundar/ep-engine,teligent-ru/ep-engine