Support redox target os with unix target family

Cargo.toml

 [package]
 name = "termion"
-version = "1.5.1"
+version = "1.5.2"
 authors = ["ticki <Ticki@users.noreply.github.com>", "gycos <alexandre.bury@gmail.com>", "IGI-111 <igi-111@protonmail.com>"]
 description = "A bindless library for manipulating terminals."
 repository = "https://gitlab.redox-os.org/redox-os/termion"

src/lib.rs

@@ -17,7 +17,7 @@ extern crate numtoa;
 #[path="sys/redox/mod.rs"]
 mod sys;
 
-#[cfg(unix)]
+#[cfg(all(unix, not(target_os = "redox")))]
 #[path="sys/unix/mod.rs"]
 mod sys;
 

src/sys/redox/tty.rs

@@ -5,7 +5,7 @@ use super::syscall;
 
 /// Is this stream a TTY?
 pub fn is_tty<T: AsRawFd>(stream: &T) -> bool {
-    if let Ok(fd) = syscall::dup(stream.as_raw_fd(), b"termios") {
+    if let Ok(fd) = syscall::dup(stream.as_raw_fd() as _, b"termios") {
         let _ = syscall::close(fd);
         true
     } else {