mfd: lp8788: Fix an error handling path in lp8788_irq_init() and lp8788_irq_init()

In lp8788_irq_init(), if an error occurs after a successful
irq_domain_add_linear() call, it must be undone by a corresponding
irq_domain_remove() call.

irq_domain_remove() should also be called in lp8788_irq_exit() for the same
reason.

Fixes: eea6b7cc53 ("mfd: Add lp8788 mfd driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/bcd5a72c9c1c383dd6324680116426e32737655a.1659261275.git.christophe.jaillet@wanadoo.fr

drivers/mfd/lp8788-irq.c

@@ -175,6 +175,7 @@ int lp8788_irq_init(struct lp8788 *lp, int irq)
 				IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 				"lp8788-irq", irqd);
 	if (ret) {
+		irq_domain_remove(lp->irqdm);
 		dev_err(lp->dev, "failed to create a thread for IRQ_N\n");
 		return ret;
 	}
@@ -188,4 +189,6 @@ void lp8788_irq_exit(struct lp8788 *lp)
 {
 	if (lp->irq)
 		free_irq(lp->irq, lp->irqdm);
+	if (lp->irqdm)
+		irq_domain_remove(lp->irqdm);
 }