remove float methods

Author: pietroalbini

RELEASES.md

@@ -53,16 +53,6 @@ These APIs are now usable in const contexts:
 - [`Duration::checked_mul`]
 - [`Duration::saturating_mul`]
 - [`Duration::checked_div`]
-- [`Duration::as_secs_f64`]
-- [`Duration::as_secs_f32`]
-- [`Duration::from_secs_f64`]
-- [`Duration::from_secs_f32`]
-- [`Duration::mul_f64`]
-- [`Duration::mul_f32`]
-- [`Duration::div_f64`]
-- [`Duration::div_f32`]
-- [`Duration::div_duration_f64`]
-- [`Duration::div_duration_f32`]
 - [`MaybeUninit::as_ptr`]
 - [`MaybeUninit::as_mut_ptr`]
 - [`MaybeUninit::assume_init`]