irqchip/jcore-aic: Fix missing allocation of IRQ descriptors

The initialization function for the J-Core AIC aic_irq_of_init() is
currently missing the call to irq_alloc_descs() which allocates and
initializes all the IRQ descriptors. Add missing function call and
return the error code from irq_alloc_descs() in case the allocation
fails.

Fixes: 981b58f66cfc ("irqchip/jcore-aic: Add J-Core AIC driver")
Signed-off-by: John Paul Adrian Glaubitz <[e-mail]>
Tested-by: Rob Landley <[e-mail]>
Signed-off-by: Marc Zyngier <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/irqchip/irq-jcore-aic.c

···
 	unsigned min_irq = JCORE_AIC2_MIN_HWIRQ;
 	unsigned dom_sz = JCORE_AIC_MAX_HWIRQ+1;
 	struct irq_domain *domain;
+	int ret;
 
 	pr_info("Initializing J-Core AIC\n");
 
···
 	jcore_aic.irq_mask = noop;
 	jcore_aic.irq_unmask = noop;
 	jcore_aic.name = "AIC";
+
+	ret = irq_alloc_descs(-1, min_irq, dom_sz - min_irq,
+			      of_node_to_nid(node));
+
+	if (ret < 0)
+		return ret;
 
 	domain = irq_domain_add_legacy(node, dom_sz - min_irq, min_irq, min_irq,
 				       &jcore_aic_irqdomain_ops,