irqchip/mbigen: Free msi_desc on device teardown

Using irq_domain_free_irqs_common() on the irqdomain free path will
leave the MSI descriptor unfreed when platform devices get removed.
Properly free it by MSI domain free function.

Fixes: 9650c60e ("irqchip/mbigen: Create irq domain for each mbigen device")
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200408114352.1604-1-yuzenghui@huawei.com

drivers/irqchip/irq-mbigen.c

@@ -220,10 +220,16 @@ static int mbigen_irq_domain_alloc(struct irq_domain *domain,
 	return 0;
 }
 
+static void mbigen_irq_domain_free(struct irq_domain *domain, unsigned int virq,
+				   unsigned int nr_irqs)
+{
+	platform_msi_domain_free(domain, virq, nr_irqs);
+}
+
 static const struct irq_domain_ops mbigen_domain_ops = {
 	.translate	= mbigen_domain_translate,
 	.alloc		= mbigen_irq_domain_alloc,
-	.free		= irq_domain_free_irqs_common,
+	.free		= mbigen_irq_domain_free,
 };
 
 static int mbigen_of_create_domain(struct platform_device *pdev,