[llvm] [TableGen] Added submulticlass typechecking to template arg values. (PR #112904)

[via llvm-commits]

jofrn wrote:

> 
> Before your patch I get:
> 
> ```
> def X {	// C
>   bit x = 1;
> }
> ```
I not am getting `bit x = 1` in the aforementioned case, I get `bit x = 0` as is now both before and after. Uploading a test to show that one needs a `!cast` to perform the correct check.


https://github.com/llvm/llvm-project/pull/112904