[llvm-branch-commits] [llvm] [SPIRV] Replace `SPIRVType` with `SPIRVTypeInst` as much as we can (PR #180721)

[Nick Sarnie via llvm-branch-commits]

https://github.com/sarnex approved this pull request.

lgtm, i didnt check every single line but the idea of using the guarded type where it doesnt currently blow up lgtm

https://github.com/llvm/llvm-project/pull/180721