Fix a typo in ToSocketAddrs documentation

Fix a typo in ToSocketAddrs documentation: s/ToSocketsAddr/ToSocketAddrs

src/libstd/net/addr.rs

@@ -759,7 +759,7 @@ fn hash<H: hash::Hasher>(&self, s: &mut H) {
 /// ```
 ///
 /// [`TcpStream::connect`] is an example of an function that utilizes
-/// `ToSocketsAddr` as a trait bound on its parameter in order to accept
+/// `ToSocketAddrs` as a trait bound on its parameter in order to accept
 /// different types:
 ///
 /// ```no_run