IPv6 RA not available when DHCP6 Relay is enabled

[MrFox]

Found a bug in the current version of the interface.

If you have DHCPv6 Relay enabled you can not change the RA settings in the page of the DHCPv6 and RA settings.
You get this message;
DHCPv6 Relay is currently enabled. Cannot enable the DHCPv6 Server service while the DHCPv6 Relay is enabled on any interface.

It also looks to have caused RA not to be sent by the router as clients on the relayed subnet do not get a gateway.

[cmb]

Good catch, thanks. Fixed.
https://redmine.pfsense.org/issues/6063