Remove stabilized feature gate

Author: bjorn3

library/std/tests/floats/lib.rs

@@ -1,4 +1,4 @@
-#![feature(f16, f128, float_gamma, float_next_up_down, float_minimum_maximum)]
+#![feature(f16, f128, float_gamma, float_minimum_maximum)]
 
 use std::fmt;
 use std::ops::{Add, Div, Mul, Rem, Sub};

library/std/tests/sync/lib.rs

@@ -2,7 +2,6 @@
 #![feature(mapped_lock_guards)]
 #![feature(mpmc_channel)]
 #![feature(once_cell_try)]
-#![feature(once_wait)]
 #![feature(lock_value_accessors)]
 #![feature(reentrant_lock)]
 #![feature(rwlock_downgrade)]