Remove unnecessary mapping from Agent drivers
Remove unnecessary mapping from Agent drivers

Both vendor methods comes from the same VendorInterface, so no need to
use the MixinVendorInterface.

Change-Id: I9d6cea289555a79f1ccb1c6698809e196e9e4255

ramineni/myironic,pshchelo/ironic,supermari0/ironic,debayanray/ironic_backup,SauloAislan/ironic,bacaldwell/ironic,faizan-barmawer/openstack_ironic,NaohiroTamura/ironic,rackerlabs/ironic,ionutbalutoiu/ironic,bacaldwell/ironic,pshchelo/ironic,openstack/ironic,naototty/vagrant-lxc-ironic,devananda/ironic,Tan0/ironic,hpproliant/ironic,naterh/ironic,ionutbalutoiu/ironic,dims/ironic,NaohiroTamura/ironic,rdo-management/ironic,froyobin/ironic,Tehsmash/ironic,SauloAislan/ironic,dims/ironic,openstack/ironic,redhat-openstack/ironic,naototty/vagrant-lxc-ironic