88e3693570
Make delegation methods of `std::net::IpAddr` unstably const Make the following methods of `std::net::IpAddr` unstable const under the `const_ip` feature: - `is_unspecified` - `is_loopback` - `is_global` - `is_multicast` Also adds a test for these methods in a const context. Possible because these methods delegate to the inner `Ipv4Addr` or `Ipv6Addr`, which were made const ([PR#76205](https://github.com/rust-lang/rust/pull/76142) and [PR#76206](https://github.com/rust-lang/rust/pull/76206)), and the recent stabilization of const control flow. Part of #76205 r? @ecstatic-morse