net: panic if too many DNS servers.

[Dirbaio]

• If the DHCP server provides more servers than smoltcp's DNS_MAX_SERVER_COUNT, panic here https://github.com/smoltcp-rs/smoltcp/blob/main/src/socket/dns.rs#L170
• hardcoded 6 here https://github.com/embassy-rs/embassy/blob/a1fce1b554bea8cad7f87073748145aaeca634f8/embassy-net/src/lib.rs#L699

we should truncate instead of panic.

temp workarond: add this feature to smoltcp.

smoltcp = { version = "0.10.0", default-features = false, features = [ "dns-max-server-count-4" ] }

[Frostie314159]

I mean it explicitly mentions, that this panics under the condition, which you described. However, introducing a check and returning a Result might be more ideal, than just panicking.

[MaikuMori]

Agree about handling this gracefully