Adjust tcp_quickack feature to allow other os::linux::net features.

library/std/src/os/android/net.rs

@@ -1,4 +1,4 @@
-//! Linux and Android-specific definitions for socket options.
+//! Android-specific networking functionality.
 
 #![unstable(feature = "tcp_quickack", issue = "96256")]
-pub use crate::os::net::tcp::TcpStreamExt;
+pub use crate::os::net::linux_ext::tcp::TcpStreamExt;

library/std/src/os/linux/net.rs

@@ -1,4 +1,4 @@
-//! Linux and Android-specific definitions for socket options.
+//! Linux-specific networking functionality.
 
 #![unstable(feature = "tcp_quickack", issue = "96256")]
-pub use crate::os::net::tcp::TcpStreamExt;
+pub use crate::os::net::linux_ext::tcp::TcpStreamExt;

library/std/src/os/net/linux_ext/mod.rs

@@ -0,0 +1,9 @@
+//! Linux and Android-specific networking functionality.
+
+#![doc(cfg(any(target_os = "linux", target_os = "android")))]
+
+#[unstable(feature = "tcp_quickack", issue = "96256")]
+pub(crate) mod tcp;
+
+#[cfg(test)]
+mod tests;

library/std/src/os/net/tests.rs → library/std/src/os/net/linux_ext/tests.rs

@@ -1,9 +1,8 @@
-#[cfg(any(target_os = "android", target_os = "linux",))]
 #[test]
 fn quickack() {
     use crate::{
         net::{test::next_test_ip4, TcpListener, TcpStream},
-        os::net::tcp::TcpStreamExt,
+        os::net::linux_ext::tcp::TcpStreamExt,
     };
 
     macro_rules! t {

library/std/src/os/net/mod.rs

@@ -1,7 +1,4 @@
-//! Linux and Android-specific definitions for socket options.
+//! OS-specific networking functionality.
 
-#![unstable(feature = "tcp_quickack", issue = "96256")]
-#![doc(cfg(any(target_os = "linux", target_os = "android",)))]
-pub mod tcp;
-#[cfg(test)]
-mod tests;
+#[cfg(any(target_os = "linux", target_os = "android", doc))]
+pub(super) mod linux_ext;