Rollup merge of #119589 - petrochenkov:cdatalock, r=Mark-Simulacrum

cstore: Remove unnecessary locking from `CrateMetadata`

Locks and atomics in `CrateMetadata` fields were necessary before rust-lang/rust#107765 when `CStore` was cloneable, but now they are not necessary and can be removed after restructuring the code a bit to please borrow checker.

All remaining locked fields in `CrateMetadata` are lazily populated caches.

Author: matthiaskrgr