KVM: PIT: free irq source id in handling error path

Free irq source id if create pit workqueue fail
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/i8254.c

@@ -697,6 +697,7 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
 	pit->wq = create_singlethread_workqueue("kvm-pit-wq");
 	if (!pit->wq) {
 		mutex_unlock(&pit->pit_state.lock);
+		kvm_free_irq_source_id(kvm, pit->irq_source_id);
 		kfree(pit);
 		return NULL;
 	}