[clang] [HLSL] Add Append/ConsumeStructuredBuffer definitions to HLSLExternalSemaSource (PR #113643)

[Greg Roth via cfe-commits]

https://github.com/pow2clk commented:

Looks good overall. I am worried about that typedbuffer enum though. Perhaps it doesn't have much impact as of yet, but perhaps we need to change some conditionals to accept structuredbuffer enums where appropriate.

https://github.com/llvm/llvm-project/pull/113643