Semantic names as part of variable names in SPIR-V code

This is mainly a suggestion or feature request. I know Semantics does not make any sense in OpenGL or Vulkan but it would be great to have an option that the glslang adds HLSL semantics to variable names.

Use Case:
In the engines which are mainly implemented based on DirectX and are supporting Vulkan now, there are some dependencies on semantic names which are hard to handle in Vulkan shaders. If an option gives the ability to annotate these variables with their semantic names, it would be great.

No files, tests, or entry points are named. First clarify how HLSL semantic names should be represented in generated SPIR-V and what option should control them; done means the option preserves the requested semantic names for applicable variables without affecting unsupported GLSL or Vulkan use cases.

Written by the indexing model from the issue text.