Auto merge of rust-lang#100390 - jhpratt:float-from-bool, r=dtolnay

Implement `From<bool>` for f32, f64

As is required for trait implementations, these are insta-stable. Given there is a release tomorrow and this needs FCP, I set 1.65 as the stable version.

`@rustbot` label +A-floating-point +C-feature-request +needs-fcp +relnotes +S-waiting-on-review +T-libs-api -T-libs

Author: bors