Rollup merge of #131405 - davidtwco:hardcoded-strip-macos, r=jieyouxu,albertlarsan68

bootstrap/codegen_ssa: ship llvm-strip and use it for -Cstrip

Fixes #131206.

- Includes `llvm-strip` (a symlink to `llvm-objcopy`) in the compiler dist artifact so that it can be used for `-Cstrip` instead of the system tooling.
- Uses `llvm-strip` instead of `/usr/bin/strip` for macOS. macOS needs a specific linker and the system one is preferred, hence #130781 but that doesn't work when cross-compiling, so use the `llvm-strip` utility instead.

cc #123151

compiler/rustc_codegen_ssa/messages.ftl

@@ -2,6 +2,8 @@ codegen_ssa_L4Bender_exporting_symbols_unimplemented = exporting symbols not imp
 
 codegen_ssa_add_native_library = failed to add native library {$library_path}: {$error}
 
+codegen_ssa_aix_strip_not_used = using host's `strip` binary to cross-compile to AIX which is not guaranteed to work
+
 codegen_ssa_apple_deployment_target_invalid =
     failed to parse deployment target specified in {$env_var}: {$error}