Rollup merge of rust-lang#74602 - poliorcetics:maybe-uninit-zeroed-doc-clarification, r=jyn514

Clarify the doc for MaybeUninit::zeroed on incorrect use

Fixes rust-lang#74343.

@rustbot modify labels: C-enhancement, T-doc

Author: Manishearth

library/core/src/mem/maybe_uninit.rs

@@ -336,8 +336,8 @@ impl<T> MaybeUninit<T> {
     /// assert_eq!(x, (0, false));
     /// ```
     ///
-    /// *Incorrect* usage of this function: initializing a struct with zero, where some fields
-    /// cannot hold 0 as a valid value.
+    /// *Incorrect* usage of this function: calling `x.zeroed().assume_init()`
+    /// when `0` is not a valid bit-pattern for the type:
     ///
     /// ```rust,no_run
     /// use std::mem::MaybeUninit;