Revert "emacs: disable native compilation on Darwin"

This reverts commit 9fc2bfda83.

As described in
https://github.com/NixOS/nixpkgs/issues/395169#issuecomment-3043599654,
native compilation once again works on macOS after libarchive was
updated to 3.8.0.

I have set this flag on an m3 macbook (ARM) and emacs seems to work just
fine.

Closes #395169.

pkgs/applications/editors/emacs/make-emacs.nix

@@ -67,11 +67,7 @@
   zlib,
 
   # Boolean flags
-
-  # FIXME: Native compilation breaks build and runtime on macOS 15.4;
-  # see <https://github.com/NixOS/nixpkgs/issues/395169>.
-  withNativeCompilation ?
-    stdenv.buildPlatform.canExecute stdenv.hostPlatform && !stdenv.hostPlatform.isDarwin,
+  withNativeCompilation ? stdenv.buildPlatform.canExecute stdenv.hostPlatform,
   noGui ? false,
   srcRepo ? true,
   withAcl ? false,