regmap: irq: Convert to use irq_domain_create_legacy()

irq_domain_create_legacy() takes a fwnode as parameter contrary to
irq_domain_add_legacy() which requires a OF node.

Switch the regmap irq domain creation to use that new function so it is not
longer limited to OF based usage.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20201030165919.86234-6-andriy.shevchenko@linux.intel.com

drivers/base/regmap/regmap-irq.c

@@ -803,13 +803,12 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode,
 	}
 
 	if (irq_base)
-		d->domain = irq_domain_add_legacy(to_of_node(fwnode),
-						  chip->num_irqs, irq_base,
-						  0, &regmap_domain_ops, d);
+		d->domain = irq_domain_create_legacy(fwnode, chip->num_irqs,
+						     irq_base, 0,
+						     &regmap_domain_ops, d);
 	else
-		d->domain = irq_domain_add_linear(to_of_node(fwnode),
-						  chip->num_irqs,
-						  &regmap_domain_ops, d);
+		d->domain = irq_domain_create_linear(fwnode, chip->num_irqs,
+						     &regmap_domain_ops, d);
 	if (!d->domain) {
 		dev_err(map->dev, "Failed to create IRQ domain\n");
 		ret = -ENOMEM;