Move the mod pipe to std::net

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

Author: NobodyXu

library/std/src/io/mod.rs

@@ -338,9 +338,6 @@ pub(crate) mod copy;
 mod cursor;
 mod error;
 mod impls;
-/// Annoymous pipe implementation
-#[unstable(feature = "annoymous_pipe", issue = "127154")]
-pub mod pipe;
 pub mod prelude;
 mod stdio;
 mod util;

library/std/src/net/mod.rs

@@ -43,6 +43,10 @@ mod tcp;
 pub(crate) mod test;
 mod udp;
 
+/// Annoymous pipe implementation
+#[unstable(feature = "annoymous_pipe", issue = "127154")]
+pub mod pipe;
+
 /// Possible values which can be passed to the [`TcpStream::shutdown`] method.
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
 #[stable(feature = "rust1", since = "1.0.0")]