Rollup merge of #155347 - balt-dev:patch-1, r=cuviper

Add push_mut and new Layout methods to release notes

As recommended by @cuviper on Zulip, I'm making a direct PR to add this.

Author: matthiaskrgr

RELEASES.md

@@ -78,6 +78,17 @@ Stabilized APIs
 - [`<*const T>::as_ref_unchecked`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.as_ref_unchecked)
 - [`<*mut T>::as_ref_unchecked`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.as_ref_unchecked-1)
 - [`<*mut T>::as_mut_unchecked`](https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.as_mut_unchecked)
+- [`Vec::push_mut`](https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#method.push_mut)
+- [`Vec::insert_mut`](https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#method.insert_mut)
+- [`VecDeque::push_front_mut`](https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.push_front_mut)
+- [`VecDeque::push_back_mut`](https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.push_back_mut)
+- [`VecDeque::insert_mut`](https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.insert_mut)
+- [`LinkedList::push_front_mut`](https://doc.rust-lang.org/stable/std/collections/struct.LinkedList.html#method.push_front_mut)
+- [`LinkedList::push_back_mut`](https://doc.rust-lang.org/stable/std/collections/struct.LinkedList.html#method.push_back_mut)
+- [`Layout::dangling_ptr`](https://doc.rust-lang.org/stable/std/alloc/struct.Layout.html#method.dangling_ptr)
+- [`Layout::repeat`](https://doc.rust-lang.org/stable/std/alloc/struct.Layout.html#method.repeat)
+- [`Layout::repeat_packed`](https://doc.rust-lang.org/stable/std/alloc/struct.Layout.html#method.repeat_packed)
+- [`Layout::extend_packed`](https://doc.rust-lang.org/stable/std/alloc/struct.Layout.html#method.extend_packed)
 
 
 These previously stable APIs are now stable in const contexts: