[llvm] [mlir] [mlir][nvvm] Expose MLIR_NVPTXCOMPILER_ENABLED in mlir-config.h. (PR #84007)

[Peiming Liu via llvm-commits]

PeimingLiu wrote:

Seems that the change exposes `'GTEST_NO_LLVM_SUPPORT' is not defined, evaluates to 0`, any idea how to fix that?

https://github.com/llvm/llvm-project/pull/84007