Problem description: it is not possible to make a Full clone of a host if during the full clone operation a template with at least one item is unlinked. In this case the "Cannot add host" error is returned.

Steps to reproduce:

1. Create a template with at least 1 item
2. Create a host and link the previously created template to it
3. Open host configuration And press "Full clone" button
4. Change the name of the host clone and unlink the template from this clone
5. Attempt to save the host clone

Result: The "Cannot add host" error is returned. Host clone is not saved.
Expected: No errors should be returned. Host clone should be saved.

Example: