Use stable #[naked] instead of global_asm!() fallback

#[naked] is stable since Rust 1.79, and origin already requires 1.88.
This removes the global_asm!() fallback which had platform-specific
.type directive syntax issues (e.g., @function vs %function on ARM).

Author: walruscraft

src/naked.rs

@@ -1,4 +1,4 @@
-//! Limited wrapper around and polyfill for the `#[naked]` attribute.
+//! Wrapper around the `#[naked]` attribute.
 //!
 //! # Example
 //!
@@ -28,10 +28,8 @@
 
 #![allow(unused_macros)]
 
-/// `#[naked]` is nightly-only. We use it when we can, and fall back to
-/// `global_asm` otherwise. This macro supports a limited subset of the
-/// features of `#[naked]`.
-#[cfg(feature = "nightly")]
+/// Wrapper around `#[naked]` for defining naked functions.
+/// This macro supports a limited subset of `#[naked]` features.
 macro_rules! naked_fn {
     (
         $doc:literal;
@@ -50,29 +48,3 @@ macro_rules! naked_fn {
         }
     };
 }
-
-/// `#[naked]` is nightly-only. We use it when we can, and fall back to
-/// `global_asm` otherwise. This macro supports a limited subset of the
-/// features of `#[naked]`.
-#[cfg(not(feature = "nightly"))]
-macro_rules! naked_fn {
-    (
-        $doc:literal;
-        $vis:vis fn $name:ident $args:tt -> $ret:ty;
-        $($code:literal),*;
-        $($label:ident = $kind:ident $path:path),*
-    ) => {
-        unsafe extern "C" {
-            #[doc = $doc]
-            $vis fn $name $args -> $ret;
-        }
-        core::arch::global_asm!(
-            concat!(".global ", stringify!($name)),
-            concat!(".type ", stringify!($name), ", @function"),
-            concat!(stringify!($name), ":"),
-            $($code),*,
-            concat!(".size ", stringify!($name), ", .-", stringify!($name)),
-            $($label = $kind $path),*
-        );
-    };
-}