How to create same subnet IP interface within host network by vagrant-libvirt

Ref. https://github.com/vagrant-libvirt/vagrant-libvirt#public-network-options

Objectives

Usually, vagrant-libvirt creates an interface within virbr* network subnet.
virt-install command can attach to host bridge network with the option "--network=bridge:br0"
How to assign a vagrant-libvirt's interface to host bridge like virt-install does?
If possible, I can access to the VM from my client notebook within KVM host network without adding routing configuration etc
And that is possible.

System

$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=16.04
DISTRIB_CODENAME=xenial
DISTRIB_DESCRIPTION="Ubuntu 16.04.2 LTS"

$ vagrant --version
Vagrant 1.8.1

$ vagrant plugin list
fog-libvirt (0.0.3)
  - Version Constraint: 0.0.3
vagrant-libvirt (0.0.35)

host network is 192.168.100.0/24 has dhcp server.
attach bridge interface "br0" on KVM host.

$ ip a s br0 | grep -Ei "br0|inet4"
8: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    inet 192.168.100.5/24 brd 192.168.100.255 scope global br0

Configure Vagrantfile

$ cat Vagrantfile
Vagrant.configure(2) do |config|
  config.vm.define :vm1 do |vm1|
    vm1.vm.box = "centos/7"
    vm1.vm.network :public_network, :type => "bridge",
      dev: "br0",
      mode: "bridge",
      network_name: "public_network"
  end
end

vagrant up

[vagrant@localhost ~]$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:00:f6:a0:c2 brd ff:ff:ff:ff:ff:ff
    inet 192.168.121.21/24 brd 192.168.121.255 scope global dynamic eth0
       valid_lft 3579sec preferred_lft 3579sec
    inet6 fe80::5054:ff:fef6:a0c2/64 scope link
       valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:00:31:b9:94 brd ff:ff:ff:ff:ff:ff
    inet 192.168.100.163/24 brd 192.168.100.255 scope global dynamic eth1
       valid_lft 578sec preferred_lft 578sec
    inet6 fe80::5054:ff:fe31:b994/64 scope link
       valid_lft forever preferred_lft forever

Confirmation

C:\WINDOWS\system32>ping 192.168.100.163

Pinging 192.168.100.163 with 32 bytes of data:
Reply from 192.168.100.163: bytes=32 time=1ms TTL=64
Reply from 192.168.100.163: bytes=32 time=2ms TTL=64
Reply from 192.168.100.163: bytes=32 time=1ms TTL=64
Reply from 192.168.100.163: bytes=32 time=2ms TTL=64

Ping statistics for 192.168.100.163:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 1ms, Maximum = 2ms, Average = 1ms