[libunwind] [libunwind] Fix compilation for the x32 ABI. (PR #116608)

[Alexander Richardson via cfe-commits]

arichardson wrote:

> > ⚠️ C/C++ code formatter, clang-format found issues in your code. ⚠️
> 
> Ok, but this is just clearly silly given the surrounding code.

Yes I would ignore this.

This change looks reasonable to me. I have no experience with the x32 parts of libunwind, but if it fixes the static_asserts it sounds good to me.

https://github.com/llvm/llvm-project/pull/116608