[llvm] MC: Refine ALIGN relocation conditions (PR #150816)

[Fangrui Song via llvm-commits]

MaskRay wrote:

> ```shell
> $ git clone git at github.com:kito-cheng/riscv-alignment-check.git
> ```

Is this repo public?

```
% git clone https://github.com/kito-cheng/riscv-alignment-check
Cloning into 'riscv-alignment-check'...
remote: Repository not found.
fatal: repository 'https://github.com/kito-cheng/riscv-alignment-check/' not found
```

https://github.com/llvm/llvm-project/pull/150816