dns: sd-resolved: fix hash table initialization
The hash table was not initialized if there was no D-Bus connection at the time of object creation.
Fixes: f70ee670 ('dns: sd-resolved: reset interface configuration on deactivation')
The hash table was not initialized if there was no D-Bus connection at the time of object creation.
Fixes: f70ee670 ('dns: sd-resolved: reset interface configuration on deactivation')