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

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: eea6b7cc53aa ("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