With the removal of mlir-vulkan-runner (as part of #73457) ine7e3c45bc7, this pass no longer has to be public (previously it had to be so the runner could use it). This commit makes it instead only available for use by mlir-opt. This is a recommit of058d183980(#124301) which had been reverted in4573c857dadue to a missing linker dependency on MLIRSPIRVTransforms in mlir/test/lib/Pass/CMakeLists.txt (fixed in this commit).