ARM64: Unable to decode `luti2` and `luti4` instructions

[TIHan]

When using cstool, I'm not able to decode ARM64 luti2 and luti4 instructions.

Here are some examples:

Hexcode: 00B02045
Should output: luti2 z0.b, { z0.b }, z0[0]
But cstool fails and stops decoding altogether.

Hexcode: 55B17545
Should output: luti2 z21.b, { z10.b }, z21[1]
But again, cstool fails and stops decoding.

[Rot127]

So after investigating it a little, I couldn't spot the problem immediately. Which means it is likely somewhere in the generated files. Because we will update to LLVM 18 soon anyway, it is better to fix it there IMHO (if it doesn't solve itself anyways). Same for #2268

[TIHan]

That makes sense. Thank you for looking at it. Will be looking forward to the LLVM 18 update.

[Rot127]

It was indeed added in LLVM-18. So this will be closed once #2298 is merged.