Revert heterogeneous SocketAddr PartialEq impls

These lead to inference regressions (mostly in tests) in code that looks
like:

    let socket = std::net::SocketAddrV4::new(std::net::Ipv4Addr::new(127, 0, 0, 1), 8080);
    assert_eq!(socket, "127.0.0.1:8080".parse().unwrap());

That compiles as of stable 1.44.0 but fails in beta with:

    error[E0284]: type annotations needed
     --> src/main.rs:3:41
      |
    3 |     assert_eq!(socket, "127.0.0.1:8080".parse().unwrap());
      |                                         ^^^^^ cannot infer type for type parameter `F` declared on the associated function `parse`
      |
      = note: cannot satisfy `<_ as std::str::FromStr>::Err == _`
    help: consider specifying the type argument in the method call
      |
    3 |     assert_eq!(socket, "127.0.0.1:8080".parse::<F>().unwrap());
      |

0 files changed, 0 insertions, 0 deletions