chronopost: Do not set location to "None" if empty
chronopost: Do not set location to "None" if empty

yannrouillard/weboob,sputnick-dev/weboob,Boussadia/weboob,willprice/weboob,RouxRC/weboob,laurent-george/weboob,nojhan/weboob-devel,Boussadia/weboob,Boussadia/weboob,yannrouillard/weboob,frankrousseau/weboob,willprice/weboob,frankrousseau/weboob,Konubinix/weboob,Konubinix/weboob,yannrouillard/weboob,RouxRC/weboob,frankrousseau/weboob,willprice/weboob,laurent-george/weboob,nojhan/weboob-devel,laurent-george/weboob,Boussadia/weboob,RouxRC/weboob,nojhan/weboob-devel,Konubinix/weboob,sputnick-dev/weboob,sputnick-dev/weboob