Description of problem:
Although we have fixed this issue - https://bugzilla.redhat.com/show_bug.cgi?id=2095967, but there are still some scenarios that the mode of the NIC is vepa:
1 Create a VM with PXE and a default network
2 Create a VM with PXE and no default network
3 Edit the network to direct

Version-Release number of selected components (if applicable):
cockpit-292-1.el8.x86_64
cockpit-machines-292-1.el8.noarch
libvirt-dbus-1.3.0-2.module+el8.8.0+16781+9f4724c2.x86_64

How reproducible:
100%

Steps to Reproduce:
1 Make sure that there is only one virtual network in the host, and it should be default, then create a VM with PXE, then check the interface element by "virsh dumpxml ${vm}"
2 Make sure that there is no virtual network in the host, then create a VM with PXE, then check the interface element by "virsh dumpxml ${vm}"
3 Create a VM by "Local install media", then enter the VM detail page, then edit the NIC to "direct" and "eno1", then check the interface element by "virsh dumpxml ${vm}"

Actual results:
1 In step 1, the mode in interface element is "vepa"
2 In step 2, the mode in interface element is "vepa"
3 In step 3, the mode in interface element is "vepa"

Expected results:
1 In step 1, the mode in interface element is "bridge"
2 In step 2, the mode in interface element is "bridge"
3 In step 3, the mode in interface element is "bridge"

Additional info: