Rollup merge of rust-lang#76029 - denisvasilik:intra-doc-links-core-atomic, r=kennytm

Move to intra-doc links for library/core/src/sync/atomic.rs

Helps with rust-lang#75080.

@rustbot modify labels: T-doc, A-intra-doc-links, T-rustdoc

Known issues:

* Link from core to std:

    [`Arc`]
	[`std::thread::yield_now`]
	[`std::thread::sleep`]
	[`std::sync::Mutex`]

Author: Dylan-DPC