[llvm] [SPIR-V] Guard against infinite loop in decorateUsesAsNonUniform (PR #208224)

[Juan Manuel Martinez Caamaño via llvm-commits]

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jmmartinez wrote:

What if instead of pushing the `ResultReg` we pushed the defining `MachineInst` (`Use`)?

The idea of doing this is to avoid doing the `MachineInstr *DefMI = MRI->getVRegDef(CurrentReg);`.

https://github.com/llvm/llvm-project/pull/208224