[NFC] Move non-upstreamed FuncParam decorations into internal::

[AGindinson]

The decorations do not exist in KhronosGroup/SPIRV-LLVM-Translator, however will interfere
with the forthcoming pulldown of SPIR-V Headers changes. Therefore, the decorations should
be moved into the dedicated internal header.

Signed-off-by: Artem Gindinson artem.gindinson@intel.com

[AlexeySachkov]

@NikitaRudenkoIntel, can we remove those FuncParam*INTEL entries or they are still used by VC backend?

[bader]

Typical contribution process for llvm-spirv tool is to commit changes to Khronos repository and pull them from there.
For pull requests like this with direct contribution, I expect justification to bypass regular process to be added to the pull request description.

[AlexeySachkov]

Typical contribution process for llvm-spirv tool is to commit changes to Khronos repository and pull them from there.
For pull requests like this with direct contribution, I expect justification to bypass regular process to be added to the pull request description.

Modified code doesn't exists in upstream, because it does not conform to any of latest versions of our published specs and was introduced as a workaround for a VC backend to enable ESIMD feature. We didn't accept it in the translator upstream so it only landed here. I would love to get rid of it completely, but I don't know if that is possible

[AGindinson]

I expect justification to bypass regular process to be added to the pull request description.

"Non-upstreamed" had been my lazy attempt to highlight the nuances @AlexeySachkov has expanded above :) I'll reflect this properly in the PR description.