Add sendmsg/recvmsg support to all supported sockets

[poscat0x04]

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[rust-log-analyzer]

The job aarch64-gnu-llvm-20-1 failed! Check out the build log: (web) (plain enhanced) (plain)

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 error: union `CmsgIter` is never used --> library/std/src/sys/net/connection/socket/unix.rs:71:11 | 71 | pub union CmsgIter<'buf> { | ^^^^^^^^ error: struct `CmsgIterInner` is never constructed --> library/std/src/sys/net/connection/socket/unix.rs:78:8 | 78 | struct CmsgIterInner<'buf> { | ^^^^^^^^^^^^^ error: struct `CmsgBuf` is never constructed --> library/std/src/sys/net/connection/socket/unix.rs:86:12 | 86 | pub struct CmsgBuf<'buf>(&'buf mut [u8]); | ^^^^^^^ error: associated functions `new` and `new_unchecked` are never used --> library/std/src/sys/net/connection/socket/unix.rs:90:12 | 88 | impl<'buf> CmsgBuf<'buf> { | ------------------------ associated functions in this implementation 89 | // fails if buf isn't aligned to alignof(cmsghdr) 90 | pub fn new(buf: &'buf mut [u8]) -> io::Result<Self> { | ^^^ ... 98 | pub unsafe fn new_unchecked(buf: &'buf mut [u8]) -> Self { | ^^^^^^^^^^^^^ error: methods `recv_msg` and `send_msg` are never used --> library/std/src/sys/net/connection/socket/unix.rs:423:12 | 128 | impl Socket { | ----------- methods in this implementation ... 423 | pub fn recv_msg<'a, 'b, T>( | ^^^^^^^^ ... 486 | pub fn send_msg<T>( | ^^^^^^^^