[PR #11555/71f8c15d backport][stable-12] Allow setting of independent custom domain for incus inventory (#11560)

Allow setting of independent custom domain for incus inventory (#11555)

Allowing the domain suffix to be appended independent of the `host_fqdn`
setting enables the inventory plugin to construct proper FQDNs if a
network has the `dns.domain` property set. Otherwise you would always
end up with something like `host01.project.local.example.net` despite
`host01.example.net` being the expected result.

(cherry picked from commit 71f8c15d2e)

Co-authored-by: Roland Sommer <rol@ndsommer.de>

plugins/inventory/incus.py

@@ -34,7 +34,8 @@ options:
     default: []
   host_domain:
     description:
-      - Domain to append to the host FQDN.
+      - Domain to append to the host.
+      - This is also used when O(host_fqdn) is not set since community.general 12.5.0.
     type: string
   host_fqdn:
     description:
@@ -170,9 +171,9 @@ class InventoryModule(BaseInventoryPlugin, Constructable):
                     if self.get_option("host_fqdn"):
                         host_name = f"{host_name}.{project}.{remote_name}"
 
-                        domain = self.get_option("host_domain")
-                        if domain:
-                            host_name = f"{host_name}.{domain}"
+                    domain = self.get_option("host_domain")
+                    if domain:
+                        host_name = f"{host_name}.{domain}"
 
                     # Add some extra variables.
                     host_vars = {}