It appears that PR https://github.com/llvm/llvm-project/pull/106429
introduced an issue for builds with SPIRV Backend target when building
with gcc, e.g.:
```
/llvm-project/llvm/lib/Target/SPIRV/SPIRVUtils.cpp:263:36: error: use of parameter from containing function
263 | llvm::SyncScope::ID SubGroup = Ctx.getOrInsertSyncScopeID("subgroup");
| ^~~
/llvm-project/llvm/lib/Target/SPIRV/SPIRVUtils.cpp:256:46: note: ‘llvm::LLVMContext& Ctx’ declared here
256 | SPIRV::Scope::Scope getMemScope(LLVMContext &Ctx, SyncScope::ID Id) {
```
This PR fixes this by removing struct and using static const variables
instead.
bbb3679ad8