[mlir][gpu] Fallback to JIT compilation

[guraypp]

Summary

Recent change introduces compilation with ptxas compiler. The change is important to be able to different versions of ptxas compiler without changing the compiler.

It causes some failures in builtbot. This change adds fallback mechanism to JIt compilation that is original path.

mlir/lib/Dialect/GPU/Transforms/SerializeToCubin.cpp

if (usePtxas) {
     // Try to compile it with ptxas first.
     std::string message;
     FailureOr<std::string> maybeCubinImage =
         compileWithPtxas(this->chip, ptxasParams, isa, dumpPtx, &message);
     if (succeeded(maybeCubinImage)) {
       return std::make_unique<std::vector<char>>(
           maybeCubinImage.value().begin(), maybeCubinImage.value().end());
     }
-    emitError(loc) << message;
-    return {};
+    llvm::errs() << message << ". It fallsback to JIT compilation.\n";
   }
 
   // Fallback to JIT compilation if ptxas fails.
   RETURN_ON_CUDA_ERROR(cuLinkAddData(
       linkState, CUjitInputType::CU_JIT_INPUT_PTX,
       const_cast<void *>(static_cast<const void *>(isa.c_str())), isa.length(),
       kernelName.c_str(), 0, /* number of jit options */
       nullptr,               /* jit options */