[llvm] [NFC][SPIR-V] Add constrainSelectedInstRegOperands helper to dedup repeating pattern in global registry (PR #208703)

[Arseniy Obolenskiy via llvm-commits]

aobolensk wrote:

> > Switched to MIB.constrainAllUses
> > As for global replacement across backends, I'll take a look at this
> 
> Wait, what replacement across backends ?

Haha, I thought that you meant to align usage across backends. Nvm

https://github.com/llvm/llvm-project/pull/208703