Add PartialOrd and Ord implementation for std::net::SocketAddr

[In-line]

Fixes #53710 continuation of #53788

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The job x86_64-gnu-llvm-5.0 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

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The job x86_64-gnu-llvm-5.0 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

[00:05:57]    Compiling alloc v0.0.0 (file:///checkout/src/liballoc)
[00:05:58]    Compiling alloc_system v0.0.0 (file:///checkout/src/liballoc_system)
[00:05:58]    Compiling panic_abort v0.0.0 (file:///checkout/src/libpanic_abort)
[00:06:02]    Compiling panic_unwind v0.0.0 (file:///checkout/src/libpanic_unwind)
[00:06:05] error[E0277]: can't compare `libc::sockaddr_in` with `_`
[00:06:05]    |
[00:06:05]    |
[00:06:05] 86 | pub struct SocketAddrV4 { inner: c::sockaddr_in }
[00:06:05]    |                           ^^^^^^^^^^^^^^^^^^^^^ no implementation for `libc::sockaddr_in < _` and `libc::sockaddr_in > _`
[00:06:05]    |
[00:06:05]    = help: the trait `core::cmp::PartialOrd<_>` is not implemented for `libc::sockaddr_in`
[00:06:05]    = note: required by `core::cmp::PartialOrd::partial_cmp`
[00:06:05] 
[00:06:05] error[E0277]: the trait bound `libc::sockaddr_in: core::cmp::Ord` is not satisfied
[00:06:05]    |
[00:06:05]    |
[00:06:05] 86 | pub struct SocketAddrV4 { inner: c::sockaddr_in }
[00:06:05]    |                           ^^^^^^^^^^^^^^^^^^^^^ the trait `core::cmp::Ord` is not implemented for `libc::sockaddr_in`
[00:06:05]    = note: required by `test/tools
31632 ./.git/modules/src/tools/lld/objects
31624 ./.git/modules/src/tools/lld/objects/pack
30300 ./src/llvm/test/Transforms

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)