Interfaces - add description to ifconfig output, closes https://github.com/opnsense/core/issues/5331
Interfaces - add description to ifconfig output, closes https://github.com/opnsense/core/issues/5331

Since -accept_rtadv is always executed, we can combine setting a description to prevent another call to ifconfig, we already need quite some calls which can slowdown configuration.
(FreeBSD 13 seems to be faster, but limiting calls in this case seems like a fair trade)

opnsense/core,opnsense/core,opnsense/core,opnsense/core,opnsense/core,opnsense/core