[ARM] Legalizer crash on `llvm.{minimum, maximum}.v2f64` if `mve` is enabled

## Reproducer

https://godbolt.org/z/1x68Ybo1z

```ll
define<2 x double> @f(<2 x double> %a, <2 x double> %b) {
%m = call <2 x double> @llvm.maximum.v2f64(<2 x double> %a, <2 x double> %b)
ret <2 x double> %m
}
```

## Command

```
llc -mtriple=thumbv8m.main-none-eabihf -mcpu=cortex-m55 maximum.ll
llc -mtriple=thumbv8m.main-none-eabihf -mcpu=cortex-m55 maximum.ll -mattr=-mve
```

## Note

The first command will hang if assertion is disabled.

`v4f32` works without crash or hang.

Start with the LLVM IR reproducer in the issue or maximum.ll and run the two provided llc commands for thumbv8m.main with and without mve. Compare the v2f64 maximum behavior with the working v4f32 case. Done means the mve-enabled command no longer crashes or hangs while producing output.

Written by the indexing model from the issue text.