[llvm] [llvm-size] Add -z option for Mach-O to exclude __PAGEZERO size. (PR #159574)

[James Henderson via llvm-commits]

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@@ -0,0 +1,60 @@
+# Test the -z option to skip __PAGEZERO segment in Mach-O files
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jh7370 wrote:

```suggestion
## Test the -z option to skip __PAGEZERO segment in Mach-O files.
```
New tests in the LLVM tools usually use double comment markers (i.e. `##`). Also, comments should end with "." per the style guide.

https://github.com/llvm/llvm-project/pull/159574