provision/docker: fix go vet issue, pass provisioner by pointer
provision/docker: fix go vet issue, pass provisioner by pointer

Endika/tsuru,guilhermebr/tsuru,kgrvamsi/tsuru,guilhermebr/tsuru,ArxdSilva/tsuru,tsuru/tsuru,4eek/tsuru,Endika/tsuru,cezarsa/tsuru,gwmoura/tsuru,gciotta/tsuru,mderaldo/tsuru,gciotta/tsuru,tuxmonteiro/tsuru,tsuru/tsuru,ggarnier/tsuru,cgvarela/tsuru,firebitsbr/tsuru,ggarnier/tsuru,ggarnier/tsuru,guilhermebr/tsuru,mderaldo/tsuru,cezarsa/tsuru,RichardKnop/tsuru,RichardKnop/tsuru,hugoantunes/tsuru,jblancett/tsuru,4eek/tsuru,jblancett/tsuru,firebitsbr/tsuru,kgrvamsi/tsuru,ArxdSilva/tsuru,Endika/tsuru,firebitsbr/tsuru,RichardKnop/tsuru,mderaldo/tsuru,cgvarela/tsuru,cezarsa/tsuru,hcxiong/tsuru,tsuru/tsuru,4eek/tsuru,tuxmonteiro/tsuru,tsuru/tsuru,jblancett/tsuru,gciotta/tsuru,tuxmonteiro/tsuru,hcxiong/tsuru,gwmoura/tsuru,cgvarela/tsuru,cezarsa/tsuru,gwmoura/tsuru,ArxdSilva/tsuru,hcxiong/tsuru,hugoantunes/tsuru,guilhermebr/tsuru,ggarnier/tsuru,ArxdSilva/tsuru,kgrvamsi/tsuru