Auto merge of #55433 - kennytm:rollup, r=kennytm

Rollup of 11 pull requests

Successful merges:

 - #55148 (Implement FromStr for PathBuf)
 - #55185 (path suggestions in Rust 2018 should point out the change in semantics)
 - #55191 (Fix sub-variant doc display)
 - #55199 (Impl items have generics)
 - #55244 (Don't rerun MIR passes when inlining)
 - #55252 (Add MaybeUninit::new)
 - #55257 (Allow extern statics with an extern type)
 - #55389 (Remove unnecessary mut in iterator.find_map documentation example, R…)
 - #55406 (Update string.rs)
 - #55412 (Fix an ICE in the min_const_fn analysis)
 - #55421 (Add ManuallyDrop::take)