ofctl.service: fix a crash on error msg
ofctl.service: fix a crash on error msg

Signed-off-by: YAMAMOTO Takashi <458bba2e4a8704776b33478100c98529b639cd9e@valinux.co.jp>
Signed-off-by: FUJITA Tomonori <93dac1fe9c4b2a3957982200319981492ad4976e@lab.ntt.co.jp>

lagopus/ryu-lagopus-ext,muzixing/ryu,mikhaelharswanto/ryu,TakeshiTseng/ryu,shinpeimuraoka/ryu,haniehrajabi/ryu,torufuru/oolhackathon,osrg/ryu,jalilm/ryu,alyosha1879/ryu,hisaharu/ryu,muzixing/ryu,mikhaelharswanto/ryu,yamt/ryu,elahejalalpour/ELRyu,lzppp/mylearning,alanquillin/ryu,OpenState-SDN/ryu,zangree/ryu,openvapour/ryu,gareging/SDN_Framework,ynkjm/ryu,torufuru/oolhackathon,habibiefaried/ryu,lzppp/mylearning,Tesi-Luca-Davide/ryu,takahashiminoru/ryu,shinpeimuraoka/ryu,yamt/ryu,castroflavio/ryu,hisaharu/ryu,TakeshiTseng/ryu,zyq001/ryu,o3project/ryu-oe,elahejalalpour/ELRyu,gopchandani/ryu,lagopus/ryu-lagopus-ext,haniehrajabi/ryu,ynkjm/ryu,jalilm/ryu,TakeshiTseng/ryu,Zouyiran/ryu,Tesi-Luca-Davide/ryu,gareging/SDN_Framework,Tejas-Subramanya/RYU_MEC,John-Lin/ryu,John-Lin/ryu,TakeshiTseng/ryu,shinpeimuraoka/ryu,lzppp/mylearning,lagopus/ryu-lagopus-ext,alanquillin/ryu,torufuru/OFPatchPanel,elahejalalpour/ELRyu,haniehrajabi/ryu,zyq001/ryu,ntts-clo/ryu,StephenKing/ryu,Tejas-Subramanya/RYU_MEC,yamt/ryu,fkakuma/ryu,habibiefaried/ryu,elahejalalpour/ELRyu,iwaseyusuke/ryu,sivaramakrishnansr/ryu,shinpeimuraoka/ryu,fujita/ryu,fkakuma/ryu,ysywh/ryu,umkcdcrg01/ryu_openflow,yamada-h/ryu,zangree/ryu,hisaharu/ryu,lsqtongxin/ryu,yamada-h/ryu,iwaseyusuke/ryu,Zouyiran/ryu,darjus-amzn/ryu,jkoelker/ryu,osrg/ryu,muzixing/ryu,yamt/ryu,lzppp/mylearning,openvapour/ryu,openvapour/ryu,ttsubo/ryu,Tejas-Subramanya/RYU_MEC,StephenKing/summerschool-2015-ryu,fkakuma/ryu,alyosha1879/ryu,darjus-amzn/ryu,TakeshiTseng/ryu,sivaramakrishnansr/ryu,ttsubo/ryu,StephenKing/summerschool-2015-ryu,John-Lin/ryu,sivaramakrishnansr/ryu,StephenKing/ryu,StephenKing/ryu,ysywh/ryu,takahashiminoru/ryu,jalilm/ryu,muzixing/ryu,Tesi-Luca-Davide/ryu,jalilm/ryu,John-Lin/ryu,fujita/ryu,gopchandani/ryu,fkakuma/ryu,gopchandani/ryu,StephenKing/ryu,Tesi-Luca-Davide/ryu,haniehrajabi/ryu,Tejas-Subramanya/RYU_MEC,Zouyiran/ryu,ntts-clo/ryu,torufuru/OFPatchPanel,osrg/ryu,iwaseyusuke/ryu,lagopus/ryu-lagopus-ext,hisaharu/ryu,ynkjm/ryu,pichuang/ryu,gopchandani/ryu,jkoelker/ryu,StephenKing/summerschool-2015-ryu,castroflavio/ryu,jkoelker/ryu,alanquillin/ryu,ysywh/ryu,OpenState-SDN/ryu,diogommartins/ryu,zyq001/ryu,jazzmes/ryu,haniehrajabi/ryu,Zouyiran/ryu,fujita/ryu,zyq001/ryu,ysywh/ryu,zangree/ryu,hisaharu/ryu,elahejalalpour/ELRyu,ttsubo/ryu,jazzmes/ryu,openvapour/ryu,castroflavio/ryu,ynkjm/ryu,Tejas-Subramanya/RYU_MEC,OpenState-SDN/ryu,gareging/SDN_Framework,gopchandani/ryu,alanquillin/ryu,lsqtongxin/ryu,o3project/ryu-oe,takahashiminoru/ryu,osrg/ryu,umkcdcrg01/ryu_openflow,gareging/SDN_Framework,takahashiminoru/ryu,darjus-amzn/ryu,diogommartins/ryu,jazzmes/ryu,diogommartins/ryu,shinpeimuraoka/ryu,lagopus/ryu-lagopus-ext,habibiefaried/ryu,ttsubo/ryu,openvapour/ryu,lzppp/mylearning,alanquillin/ryu,habibiefaried/ryu,zangree/ryu,zangree/ryu,evanscottgray/ryu,evanscottgray/ryu,pichuang/ryu,sivaramakrishnansr/ryu,darjus-amzn/ryu,iwaseyusuke/ryu,umkcdcrg01/ryu_openflow,evanscottgray/ryu,Zouyiran/ryu,StephenKing/ryu,John-Lin/ryu,alyosha1879/ryu,torufuru/oolhackathon,OpenState-SDN/ryu,zyq001/ryu,ntts-clo/mld-ryu,osrg/ryu,jalilm/ryu,umkcdcrg01/ryu_openflow,pichuang/ryu,umkcdcrg01/ryu_openflow,habibiefaried/ryu,alyosha1879/ryu,takahashiminoru/ryu,StephenKing/summerschool-2015-ryu,sivaramakrishnansr/ryu,pichuang/ryu,gareging/SDN_Framework,pichuang/ryu,ntts-clo/mld-ryu,OpenState-SDN/ryu,muzixing/ryu,StephenKing/summerschool-2015-ryu,fujita/ryu,ysywh/ryu,yamt/ryu,lsqtongxin/ryu,darjus-amzn/ryu,lsqtongxin/ryu,diogommartins/ryu,iwaseyusuke/ryu,fujita/ryu,fkakuma/ryu,Tesi-Luca-Davide/ryu,ynkjm/ryu,ttsubo/ryu,diogommartins/ryu,lsqtongxin/ryu