[TIR] Update LowerDeviceKernelLaunch to avoid kIsHostFunc

Update to use the `tvm::tir::IsHostFunc` utility function, rather than
the `kIsHostFunc` attribute.  Per discussion on
apache#14020, the `kIsHostFunct` attribute
should only be used in `BindTarget`, and should not be re-introduced
in `SplitHostDevice`.

src/tir/transforms/lower_device_kernel_launch.cc

@@ -64,12 +64,11 @@ struct KernelInfo {
  */
 class DeviceInfoCollector : public StmtVisitor {
  public:
-  static KernelInfo Collect(const GlobalVar& gvar, const PrimFuncNode* func) {
+  static KernelInfo Collect(const GlobalVar& gvar, const PrimFunc& func) {
     DeviceInfoCollector collector;
     collector.info_.target = [&]() -> Target {
       auto target_attr = func->GetAttr<Target>(tvm::attr::kTarget).value();
-      bool is_host_func =
-          func->GetAttr<Bool>(tvm::tir::attr::kIsHostFunc).value_or(Bool(false))->value;
+      bool is_host_func = IsHostFunc(func).value_or(false);
       if (is_host_func) {
         if (auto target_host = target_attr->GetHost()) {
           return target_host.value();
@@ -291,8 +290,8 @@ Pass LowerDeviceKernelLaunch() {
     auto mutator = [&mod]() {
       std::unordered_map<const GlobalVarNode*, KernelInfo> device_info_map;
       for (const auto& [gvar, base_func] : mod->functions) {
-        if (auto* prim_func = base_func.as<PrimFuncNode>()) {
-          device_info_map[gvar.get()] = DeviceInfoCollector::Collect(gvar, prim_func);
+        if (auto prim_func = base_func.as<PrimFunc>()) {
+          device_info_map[gvar.get()] = DeviceInfoCollector::Collect(gvar, prim_func.value());
         }
       }
       return DeviceKernelMutator(std::move(device_info_map));