docs (oracle-oci): add description and example for create_vnic_details
docs (oracle-oci): add description and example for create_vnic_details

ricardclau/packer,hashicorp/packer,rnaveiras/packer,rnaveiras/packer,mitchellh/packer,hashicorp/packer,mitchellh/packer,pecigonzalo/packer,ricardclau/packer,ricardclau/packer,mitchellh/packer,pecigonzalo/packer,rnaveiras/packer,mitchellh/packer,rnaveiras/packer,mitchellh/packer,hashicorp/packer,ricardclau/packer,rnaveiras/packer,pecigonzalo/packer,pecigonzalo/packer,ricardclau/packer,hashicorp/packer,rnaveiras/packer,ricardclau/packer