Use imported last_os_error

Author: newpavlov

src/linux_android_with_fallback.rs

@@ -91,10 +91,7 @@ fn futex_wait() {
     debug_assert!({
         match ret {
             0 => true,
-            -1 => {
-                let err = crate::util_libc::last_os_error();
-                err.raw_os_error() == Some(libc::EAGAIN)
-            }
+            -1 => last_os_error().raw_os_error() == Some(libc::EAGAIN),
             _ => false,
         }
     });
@@ -158,7 +155,7 @@ fn wait_until_rng_ready() -> Result<(), Error> {
             debug_assert_eq!(res, 1);
             break Ok(());
         }
-        let err = crate::util_libc::last_os_error();
+        let err = last_os_error();
         match err.raw_os_error() {
             Some(libc::EINTR) | Some(libc::EAGAIN) => continue,
             _ => break Err(err),