KVM: destroy workqueue on kvm_create_pit() failures

kernel needs to destroy workqueue if kvm_create_pit() fails, otherwise
after pit is freed, the workqueue is leaked.

Signed-off-by: Xiaotian Feng <[email protected]>
Cc: Avi Kivity <[email protected]>
Cc: Marcelo Tosatti <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Gleb Natapov <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
Cc: Gregory Haskins <[email protected]>
Signed-off-by: Avi Kivity <[email protected]>

Author: Xiaotian Feng

arch/x86/kvm/i8254.c

@@ -742,7 +742,7 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
 	kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
 	kvm_unregister_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier);
 	kvm_free_irq_source_id(kvm, pit->irq_source_id);
-
+	destroy_workqueue(pit->wq);
 	kfree(pit);
 	return NULL;
 }