Rollup merge of #136986 - ehuss:library-unsafe-fun, r=Noratrieb

Apply unsafe_op_in_unsafe_fn to the standard library

This applies unsafe_op_in_unsafe_fn to the standard library in preparation for updating to Rust 2024.

Closes rust-lang/rust#127747 (I think?) cc ``@workingjubilee``
I have been testing a variety of targets, and I feel like they are all pretty much covered. I'll continue doing some testing async, but I don't expect to catch any more.

Author: matthiaskrgr

tests/fail/panic/panic_abort1.rs

@@ -1,6 +1,6 @@
 //@error-in-other-file: the program aborted execution
 //@normalize-stderr-test: "\| +\^+" -> "| ^"
-//@normalize-stderr-test: "libc::abort\(\);|core::intrinsics::abort\(\);" -> "ABORT();"
+//@normalize-stderr-test: "unsafe \{ libc::abort\(\); \}|core::intrinsics::abort\(\);" -> "ABORT();"
 //@compile-flags: -C panic=abort
 
 fn main() {

tests/fail/panic/panic_abort2.rs

@@ -1,6 +1,6 @@
 //@error-in-other-file: the program aborted execution
 //@normalize-stderr-test: "\| +\^+" -> "| ^"
-//@normalize-stderr-test: "libc::abort\(\);|core::intrinsics::abort\(\);" -> "ABORT();"
+//@normalize-stderr-test: "unsafe \{ libc::abort\(\); \}|core::intrinsics::abort\(\);" -> "ABORT();"
 //@compile-flags: -C panic=abort
 
 fn main() {

tests/fail/panic/panic_abort3.rs

@@ -1,6 +1,6 @@
 //@error-in-other-file: the program aborted execution
 //@normalize-stderr-test: "\| +\^+" -> "| ^"
-//@normalize-stderr-test: "libc::abort\(\);|core::intrinsics::abort\(\);" -> "ABORT();"
+//@normalize-stderr-test: "unsafe \{ libc::abort\(\); \}|core::intrinsics::abort\(\);" -> "ABORT();"
 //@compile-flags: -C panic=abort
 
 fn main() {

tests/fail/panic/panic_abort4.rs

@@ -1,6 +1,6 @@
 //@error-in-other-file: the program aborted execution
 //@normalize-stderr-test: "\| +\^+" -> "| ^"
-//@normalize-stderr-test: "libc::abort\(\);|core::intrinsics::abort\(\);" -> "ABORT();"
+//@normalize-stderr-test: "unsafe \{ libc::abort\(\); \}|core::intrinsics::abort\(\);" -> "ABORT();"
 //@compile-flags: -C panic=abort
 
 fn main() {