[clang] [llvm] [openmp] [Libomptarget] Statically link all plugin runtimes (PR #87009)

[via llvm-commits]

dhruvachak wrote:

Some OMPT variables with the same name used to be present in both libomptarget and the common plugin interface. These should probably be re-worked in the new scheme of static linking? e.g. 
llvm::omp::target::ompt::Initialized

https://github.com/llvm/llvm-project/pull/87009