[clang] [AArch64] Change the coercion type of structs with pointer members. (PR #135064)

[Vitaly Buka via cfe-commits]

vitalybuka wrote:

> The tests fail with SIGSEGV without hwasan, so there is some problem revealed by this change either in the compiler or in the tests. Bailing out under hwasan is not a fix.
> 
> Disallowing function pointers makes the problem go away, so might be a useful hint. Another hint is that the issue seems to be limited to 128-bit structs only.
> 
> We are trying to cook a standalone reproducer.

@eaeltsin Isn't the original issue are new SIGSEGV on non-hwasan arm builds? 

https://github.com/llvm/llvm-project/pull/135064