[clang] [HLSL] Implement `SpirvType` and `SpirvOpaqueType` (PR #134034)

[Kazu Hirata via cfe-commits]

kazutakahirata wrote:

@cassiebeckley I'm getting the following warnings in lldb.  Would you mind taking a look?  Thanks!

```
lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:4137:11: error: enumeration value 'HLSLInlineSpirv' not handled in switch [-Werror,-Wswitch]
 4137 |   switch (qual_type->getTypeClass()) {
      |           ^~~~~~~~~~~~~~~~~~~~~~~~~
lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:4844:11: error: enumeration value 'HLSLInlineSpirv' not handled in switch [-Werror,-Wswitch]
 4844 |   switch (qual_type->getTypeClass()) {
      |           ^~~~~~~~~~~~~~~~~~~~~~~~~
lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:5142:11: error: enumeration value 'HLSLInlineSpirv' not handled in switch [-Werror,-Wswitch]
 5142 |   switch (qual_type->getTypeClass()) {
      |           ^~~~~~~~~~~~~~~~~~~~~~~~~
3 errors generated.
```


https://github.com/llvm/llvm-project/pull/134034