use_vcenter == false --> net_provider == 'neutron' use_vcenter == true --> net_provider == 'nova-network' (i.e. net_provider != 'neutron')
in both cases the result of a boolean operation is true
use_vcenter == false --> net_provider == 'neutron'
use_vcenter == true --> net_provider == 'nova-network' (i.e. net_provider != 'neutron')
in both cases the result of a boolean operation is true