[Samba] Samba + Bind + dhcpd - IP address with multiple PTR records

[Sebastian Arcus]

I posted here sometime in November last year about an install where dns 
A records kept on ending up with multiple IP addresses. Rowland kindly 
updated the script found in the wiki at:

https://wiki.samba.org/index.php/Configure_DHCP_to_update_DNS_records

and that is all fixed. I have just stumbled over a Samba install today 
which has the problem - but the other way. An IP address has multiple 
PTR records - and the current script (0.9.5) seems to just leave them in 
the dns back end.

Is it possible to update the script to also check and purge multiple PTR 
records - like it does with the A records?

Some info about my setup, in case it helps:

Slackware 64 bit - kernel 4.4.217
Samba 4.15.5
Bind 9.16.27
dhcp 4.4.2