lantiq: fix a regression in the eiu irq loading code

this worked in 3.18 but broke at some point. the old code that loaded a
irq table was incorrewct anyhow as it mapped the irqs int he domain which
should really be done when the driver using them loads them and not the
irq driver itself.

Signed-off-by: John Crispin <john@phrozen.org>

target/linux/lantiq/patches-4.4/0047-irq-fixes.patch

+--- a/arch/mips/lantiq/irq.c
++++ b/arch/mips/lantiq/irq.c
+@@ -67,7 +67,7 @@
+ #endif
+ 
+ static int exin_avail;
+-static struct resource ltq_eiu_irq[MAX_EIU];
++static u32 ltq_eiu_irq[MAX_EIU];
+ static void __iomem *ltq_icu_membase[MAX_IM];
+ static void __iomem *ltq_eiu_membase;
+ static struct irq_domain *ltq_domain;
+@@ -76,7 +76,7 @@
+ int ltq_eiu_get_irq(int exin)
+ {
+ 	if (exin < exin_avail)
+-		return ltq_eiu_irq[exin].start;
++		return ltq_eiu_irq[exin];
+ 	return -1;
+ }
+ 
+@@ -128,7 +128,7 @@
+ 	int i;
+ 
+ 	for (i = 0; i < MAX_EIU; i++) {
+-		if (d->hwirq == ltq_eiu_irq[i].start) {
++		if (d->hwirq == ltq_eiu_irq[i]) {
+ 			int val = 0;
+ 			int edge = 0;
+ 
+@@ -176,7 +176,7 @@
+ 
+ 	ltq_enable_irq(d);
+ 	for (i = 0; i < MAX_EIU; i++) {
+-		if (d->hwirq == ltq_eiu_irq[i].start) {
++		if (d->hwirq == ltq_eiu_irq[i]) {
+ 			/* by default we are low level triggered */
+ 			ltq_eiu_settype(d, IRQF_TRIGGER_LOW);
+ 			/* clear all pending */
+@@ -198,7 +198,7 @@
+ 
+ 	ltq_disable_irq(d);
+ 	for (i = 0; i < MAX_EIU; i++) {
+-		if (d->hwirq == ltq_eiu_irq[i].start) {
++		if (d->hwirq == ltq_eiu_irq[i]) {
+ 			/* disable */
+ 			ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INEN) & ~BIT(i),
+ 				LTQ_EIU_EXIN_INEN);
+@@ -343,10 +343,10 @@
+ 		return 0;
+ 
+ 	for (i = 0; i < exin_avail; i++)
+-		if (hw == ltq_eiu_irq[i].start)
++		if (hw == ltq_eiu_irq[i])
+ 			chip = &ltq_eiu_type;
+ 
+-	irq_set_chip_and_handler(hw, chip, handle_level_irq);
++	irq_set_chip_and_handler(irq, chip, handle_level_irq);
+ 
+ 	return 0;
+ }
+@@ -441,14 +441,14 @@
+ 	eiu_node = of_find_compatible_node(NULL, NULL, "lantiq,eiu-xway");
+ 	if (eiu_node && !of_address_to_resource(eiu_node, 0, &res)) {
+ 		/* find out how many external irq sources we have */
+-		exin_avail = of_irq_count(eiu_node);
++		exin_avail = of_property_count_u32_elems(eiu_node, "lantiq,eiu-irqs");
+ 
+ 		if (exin_avail > MAX_EIU)
+ 			exin_avail = MAX_EIU;
+ 
+-		ret = of_irq_to_resource_table(eiu_node,
++		ret = of_property_read_u32_array(eiu_node, "lantiq,eiu-irqs",
+ 						ltq_eiu_irq, exin_avail);
+-		if (ret != exin_avail)
++		if (ret)
+ 			panic("failed to load external irq resources");
+ 
+ 		if (!request_mem_region(res.start, resource_size(&res),