Merge bitcoin/bitcoin#33378: Remove unnecessary casts when calling socket operations

67f632b6de net: remove unnecessary casts in socket operations (Matthew Zipkin)

Pull request description:

  During review of https://github.com/bitcoin/bitcoin/pull/32747 several casting operations were questioned in existing code that had been copied or moved. That lead me to find a few other similar casts in the codebase.

  It turns out that since the `Sock` class wraps syscalls with its own internal casting (see https://github.com/bitcoin/bitcoin/pull/24357 and https://github.com/bitcoin/bitcoin/pull/20788 written in 2020-2022) we no longer need to cast the arguments when calling these functions. The original argument-casts are old and were cleaned up a bit in https://github.com/bitcoin/bitcoin/pull/12855 written in 2018.

  The casting is only needed for windows compatibility, where those syscalls require a data argument to be of type `char*` specifically:

  https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-getsockopt

  ```
  int getsockopt(
    [in]      SOCKET s,
    [in]      int    level,
    [in]      int    optname,
    [out]     char   *optval,
    [in, out] int    *optlen
  );
  ```

  but on POSIX the argument is `void*`:

  https://www.man7.org/linux/man-pages/man2/getsockopt.2.html

  ```
         int getsockopt(socklen *restrict optlen;
                        int sockfd, int level, int optname,
                        void optval[_Nullable restrict *optlen],
                        socklen_t *restrict optlen);
  ```

ACKs for top commit:
  Raimo33:
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  achow101:
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  hodlinator:
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  vasild:
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  davidgumberg:
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Tree-SHA512: c326d7242698b8d4d019f630fb6281398da2773c4e5aad1e3bba093a012c2119ad8815f42bd009e61a9a90db9b8e6ed5c75174aac059c9df83dd3aa5618a9ba6

src/test/sock_tests.cpp

@@ -24,7 +24,7 @@ static bool SocketIsClosed(const SOCKET& s)
     // wrongly pretend that the socket is not closed.
     int type;
     socklen_t len = sizeof(type);
-    return getsockopt(s, SOL_SOCKET, SO_TYPE, (sockopt_arg_type)&type, &len) == SOCKET_ERROR;
+    return getsockopt(s, SOL_SOCKET, SO_TYPE, reinterpret_cast<char*>(&type), &len) == SOCKET_ERROR;
 }
 
 static SOCKET CreateSocket()