Rollup merge of #130518 - scottmcm:stabilize-controlflow-extra, r=dtolnay

Stabilize the `map`/`value` methods on `ControlFlow`

And fix the stability attribute on the `pub use` in `core::ops`.

libs-api in https://github.com/rust-lang/rust/issues/75744#issuecomment-2231214910 seemed reasonably happy with naming for these, so let's try for an FCP.

Summary:
```rust
impl<B, C> ControlFlow<B, C> {
    pub fn break_value(self) -> Option<B>;
    pub fn map_break<T>(self, f: impl FnOnce(B) -> T) -> ControlFlow<T, C>;
    pub fn continue_value(self) -> Option<C>;
    pub fn map_continue<T>(self, f: impl FnOnce(C) -> T) -> ControlFlow<B, T>;
}
```

Resolves #75744

``@rustbot`` label +needs-fcp +t-libs-api -t-libs

---

Aside, in case it keeps someone else from going down the same dead end: I looked at the `{break,continue}_value` methods and tried to make them `const` as part of this, but that's disallowed because of not having `const Drop`, so put it back to not even unstably-const.

compiler/rustc_hir_analysis/src/lib.rs

@@ -62,7 +62,6 @@ This API is completely unstable and subject to change.
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
 #![feature(assert_matches)]
-#![feature(control_flow_enum)]
 #![feature(if_let_guard)]
 #![feature(iter_intersperse)]
 #![feature(let_chains)]