add #[allow(deprecated)] annotations

allow using deprecated functions and data structures
in deprecated functions

src/header/sys_time/mod.rs

@@ -69,6 +69,7 @@ pub struct timezone {
 /// The `getitimer()` function was marked obsolescent in the Open Group Base
 /// Specifications Issue 7, and removed in Issue 8.
 #[deprecated]
+#[allow(deprecated)]
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn getitimer(which: c_int, value: *mut itimerval) -> c_int {
     Sys::getitimer(which, unsafe { &mut *value })
@@ -100,6 +101,7 @@ pub unsafe extern "C" fn gettimeofday(tp: *mut timeval, tzp: *mut timezone) -> c
 /// The `setitimer()` function was marked obsolescent in the Open Group Base
 /// Specifications Issue 7, and removed in Issue 8.
 #[deprecated]
+#[allow(deprecated)]
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn setitimer(
     which: c_int,