[clang] [llvm] [win][aarch64] Always reserve frame pointers for Arm64 Windows (PR #146582)

[David Spickett via llvm-commits]

DavidSpickett wrote:

I've reverted this due to a test failure on our Linux bots: https://lab.llvm.org/buildbot/#/builders/17/builds/9292

And if I understand correctly, flang needs another patch before it can build properly on Windows:
```
FAILED: include/flang/__fortran_builtins.mod C:/Users/tcwg/llvm-worker/flang-arm64-windows-msvc/build/include/flang/__fortran_builtins.mod 
C:\WINDOWS\system32\cmd.exe /C "cd /D C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\tools\flang\tools\f18 && C:\Users\tcwg\scoop\apps\cmake\3.29.2\bin\cmake.exe -E make_directory C:/Users/tcwg/llvm-worker/flang-arm64-windows-msvc/build/include/flang && C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\flang.exe -cpp -fsyntax-only -module-dir C:/Users/tcwg/llvm-worker/flang-arm64-windows-msvc/build/include/flang C:/Users/tcwg/llvm-worker/flang-arm64-windows-msvc/llvm-project/flang/module/__fortran_builtins.f90"
error: invalid value 'reserved' in '-mframe-pointer=reserved'
```
As covered by https://github.com/llvm/llvm-project/issues/146802.

https://github.com/llvm/llvm-project/pull/146582