SocketAddr based on smoltcp's IpAddress
There is no unspecified ip address as smoltcp's Address and IpEndpoint does.
It's more like the std SocketAddr but can be used in environments that std is not available.
cargo test --no-default-features --features=proto-ipv4
cargo test --no-default-features --features=proto-ipv6
cargo test --no-default-features --features=proto-ipv4,proto-ipv6
cargo test --no-default-features --features=proto-ipv4,proto-ipv6,std
standard version
npx standard-version --dry-run