irqchip/irq-brcmstb-l2: Set IRQ_LEVEL for level triggered interrupts

When support for the level triggered interrupt controller flavor was
added with c0ca7262088e, we forgot to update the flags to be set to
contain IRQ_LEVEL. While the flow handler is correct, the output from
/proc/interrupts does not show such interrupts as being level triggered
when they are, correct that.

Fixes: c0ca7262088e ("irqchip/brcmstb-l2: Add support for the BCM7271 L2 controller")
Signed-off-by: Florian Fainelli <[e-mail]>
Reviewed-by: Philippe Mathieu-Daudé <[e-mail]>
Signed-off-by: Marc Zyngier <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/irqchip/irq-brcmstb-l2.c

···
 					  *init_params)
 {
 	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+	unsigned int set = 0;
 	struct brcmstb_l2_intc_data *data;
 	struct irq_chip_type *ct;
 	int ret;
···
 	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
 		flags |= IRQ_GC_BE_IO;
 
+	if (init_params->handler == handle_level_irq)
+		set |= IRQ_LEVEL;
+
 	/* Allocate a single Generic IRQ chip for this node */
 	ret = irq_alloc_domain_generic_chips(data->domain, 32, 1,
-			np->full_name, init_params->handler, clr, 0, flags);
+			np->full_name, init_params->handler, clr, set, flags);
 	if (ret) {
 		pr_err("failed to allocate generic irq chip\n");
 		goto out_free_domain;