Description of problem:
If creating a network without DHCP, the VM whose network interface is from this network will not get the IP address automatically. So, maybe a notification shown on the Network creation dialog is needed, to make the user notice that.

Version-Release number of selected component (if applicable):
cockpit-machines-208-1.el8.noarch
libvirt-dbus-1.2.0-3.module+el8.1.0+4066+0f1aadab.x86_64

How reproducible:
100%

Steps to Reproduce:
1. Create a network without setting DHCP
2. Create a VM with using the network interface from the network which is created in step 1

Actual results:
1. There is no notification shown on the network creation dialog, and the VM will not get the IP address

Expected results:
1. There is a notification shown on the network creation dialog to make the user notice that

Additional info: