Clean up on the nn_stream state machine.
Clean up on the nn_stream state machine.

Signed-off-by: Martin Sustrik <4dd6061be1198639e8b05ce4fd5ead7a0dcaa0f4@250bpm.com>

wfxiang08/nanomsg,nirs/nanomsg,simplestbest/nanomsg,pakozm/nanomsg,featherweight/ftw-kernel-nanomsg,pch957/nanomsg,cosin2008/nanomsg.NET,smithed/nanomsg,reqshark/nanomsg,imp/nanomsg,JackDunaway/featherweight-nanomsg,modulexcite/nanomsg,pakozm/nanomsg,krafczyk/nanomsg,wirebirdlabs/featherweight-nanomsg,tempbottle/nanomsg,wfxiang08/nanomsg,pch957/nanomsg,cosin2008/nanomsg.NET,JackDunaway/featherweight-nanomsg,modulexcite/nanomsg,ttyangf/nanomsg,gdamore/mamomsg,zerotacg/nanomsg,linearregression/nanomsg,imp/nanomsg,gdamore/mamomsg,linearregression/nanomsg,snikulov/nanomsg,potatogim/nanomsg,imp/nanomsg,wfxiang08/nanomsg,TTimo/nanomsg,snikulov/nanomsg,wirebirdlabs/featherweight-nanomsg,nirs/nanomsg,pch957/nanomsg,reqshark/nanomsg,hyperfact/nanomsg,yan97ao/nanomsg,kaostao/nanomsg,smithed/nanomsg,JackDunaway/featherweight-nanomsg,yan97ao/nanomsg,hyperfact/nanomsg,krafczyk/nanomsg,gdamore/mamomsg,modulexcite/nanomsg,wirebirdlabs/featherweight-nanomsg,thisco-de/nanomsg,cosin2008/nanomsg.NET,ttyangf/nanomsg,potatogim/nanomsg,ttyangf/nanomsg,TTimo/nanomsg,reqshark/nanomsg,linearregression/nanomsg,TTimo/nanomsg,zerotacg/nanomsg,kaostao/nanomsg,kaostao/nanomsg,pakozm/nanomsg,featherweight/ftw-kernel-nanomsg,tempbottle/nanomsg,simplestbest/nanomsg,TTimo/nanomsg,thisco-de/nanomsg,krafczyk/nanomsg,potatogim/nanomsg,kaostao/nanomsg,smithed/nanomsg,zerotacg/nanomsg,simplestbest/nanomsg,yan97ao/nanomsg,hyperfact/nanomsg,nirs/nanomsg,smithed/nanomsg,tempbottle/nanomsg,ttyangf/nanomsg