Really set the default max protocol to SMB2

Ticket: #5173

Conflicts:
	gui/services/migrations/0109_auto__add_field_dynamicdns_ddns_ipserver.py
	gui/services/migrations/0114_auto__add_lldp.py
	gui/services/migrations/0116_auto__chg_field_afp_afp_srv_dbpath.py
	gui/services/migrations/0118_auto__add_field_cifs_cifs_srv_domain_logons.py