de-promote Duration::from_secs

Author: RalfJung

src/libcore/time.rs

@@ -152,7 +152,6 @@ impl Duration {
     /// ```
     #[stable(feature = "duration", since = "1.3.0")]
     #[inline]
-    #[rustc_promotable]
     #[rustc_const_stable(feature = "duration_consts", since = "1.32.0")]
     pub const fn from_secs(secs: u64) -> Duration {
         Duration { secs, nanos: 0 }