irq: error missed ifndef CONFIG_HAVE_SPARSE_IRQ

An error return from create_irq_nr() is 0, but an error return from
create_irq() is -1.
Signed-off-by: NDean Nelson <dcn@sgi.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

drivers/pci/htirq.c

@@ -144,7 +144,7 @@ int __ht_create_irq(struct pci_dev *dev, int idx, ht_irq_update_t *update)
 #else
 	irq = create_irq();
 #endif
-	if (irq == 0) {
+	if (irq <= 0) {
 		kfree(cfg);
 		return -EBUSY;
 	}