Fix GS stream types (#428)
Fix GS stream types (#428)

The code in `DeclRefType::Create` was treating all of the point/line/triangle output stream types as `HLSLPointStreamType`, which meant we always output GLSL geometry shaders with `layout(points) out;`.
shader-slang/slang,csyonghe/slang,shader-slang/slang,shader-slang/slang,csyonghe/slang,csyonghe/slang