OCPBUGS-49995: Added state:down important notice to No IP address

Author: dfitzmau

modules/virt-example-nmstate-IP-management.adoc

@@ -51,6 +51,11 @@ The following snippet ensures that the interface has no IP address:
 # ...
 ----
 
+[IMPORTANT]
+====
+Always set the `state` parameter to `up` when you set both the `ipv4.enabled` and the `ipv6.enabled` parameter to `false` to disable an interface. If you set `state: down` with this configuration, the interface receives a DHCP IP address because of automatic DHCP assignment. 
+====
+
 [id="virt-example-nmstate-IP-management-dhcp_{context}"]
 == Dynamic host configuration