qemu.cfg.host-kernel: Set nettype to bridge when vhost used

vhost only works nettype = bridge
Signed-off-by: NFeng Yang <fyang@redhat.com>

qemu/cfg/host-kernel.cfg

@@ -95,6 +95,7 @@ variants:
                     query_cmd = "cat /sys/kernel/mm/ksm/pages_sharing"
                 virtio_net:
                     vhost = "vhost=on"
+                    nettype = bridge
                     # enable_vhostfd only works with vhost=on
                     enable_vhostfd = yes
                 Win2008, Win2008r2, Win7:
@@ -141,6 +142,7 @@ variants:
                     cpu_model_flags += ",hv_relaxed"
                 virtio_net:
                     vhost = "vhost=on"
+                    nettype = birdge
                     # enable_vhostfd only works with vhost=on
                     enable_vhostfd = yes
                 monitor_cmds_check.qmp: