[llvm] [AArch64][ABI] Pass v8f32 on the stack (PR #69729)

[via llvm-commits]

vfdff wrote:

> This looks weird. How come this hasn't been hit before?

I think this may be related to the data type width, where the data type `v8f32` is a 256-bit fixed-point vector type, and we rarely use such data types directly as parameters or return values. Generally, the width of the fixed-point vector data type is 128 bits, which can be placed in the `V register` on AArch64.

https://github.com/llvm/llvm-project/pull/69729