[clang] [clang-tools-extra] Remove ^^ as a token in OpenCL (PR #108224)

[via cfe-commits]

cor3ntin wrote:

The changes to the lexer look fine.

I do have a question though
Both the OpenCL 3.0 2.0 "C language specification" mention "^^ as being reserved" (https://registry.khronos.org/OpenCL/specs/3.0-unified/html/OpenCL_API.html)

However it does not appear to be the case - in the OpenCL 2.0 specification for c++ 
https://registry.khronos.org/OpenCL/specs/2.2/html/OpenCL_Cxx.html
and it is not clear to me what the support in 3.0 is supposed to be ( no mention in https://github.com/KhronosGroup/Khronosdotorg/blob/main/api/opencl/assets/CXX_for_OpenCL.pdf )
 

https://github.com/llvm/llvm-project/pull/108224