Missing attr.h from previous patch added.
Missing attr.h from previous patch added.

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

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