#4486 Log changes on DHCP add_file

[Federico Nebiolo]

DHCP module does not save changes (for diffing and rollback) when add_file is used.
Lock is always granted on dhcpd_conf only, and modifies to other files are not traced.
A quick workaround, tested on save_host.cgi, is to add proper lock_ and unlock_ directives for additional file, but I guess this should be somehow validated and/or the file to lock should be selected accordingly.
Many thanks!

[Jamie Cameron]

Thanks for pointing this out - this will be fixed in the next Webmin release.