ksmbd-tools: Add a mDNS TXT record for the ksmbd service

ksmbd-tools: Add a mDNS TXT record for the ksmbd service

MacOS ignores Bonjour services for which TXT records are not returned. This changes forces umdns service to return a TXT record (`daemon=ksmbd`) for the ksmbd service. The exact content is unimportant and to the best of my knowledge nothing reads the `daemon` tag.

Symptoms of the problem (which are also debugging steps):
* Finder refuses to open the OpenWRT "computer" in the Network list.
* Discovery.app (Bonjour Browser) lists the _ssh._tcp service, but the submenu for it doesn't unfold and no address is shown.
* `dns-sd -L OpenWrt _smb._tcp` doesn't return any address.

Signed-off-by: Kirill Nikolaev <redacted>