irqchip/crossbar: Fix incorrect type of register size

The 'size' variable is unsigned according to the dt-bindings.
As this variable is used as integer in other places, create a new variable
that allows to fix the following sparse issue (-Wtypesign):

  drivers/irqchip/irq-crossbar.c:279:52: warning: incorrect type in argument 3 (different signedness)
  drivers/irqchip/irq-crossbar.c:279:52:    expected unsigned int [usertype] *out_value
  drivers/irqchip/irq-crossbar.c:279:52:    got int *<noident>
Signed-off-by: Franck Demathieu <fdemathieu@gmail.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

drivers/irqchip/irq-crossbar.c

@@ -199,7 +199,7 @@ static const struct irq_domain_ops crossbar_domain_ops = {
 static int __init crossbar_of_init(struct device_node *node)
 {
 	int i, size, reserved = 0;
-	u32 max = 0, entry;
+	u32 max = 0, entry, reg_size;
 	const __be32 *irqsr;
 	int ret = -ENOMEM;
 
@@ -276,9 +276,9 @@ static int __init crossbar_of_init(struct device_node *node)
 	if (!cb->register_offsets)
 		goto err_irq_map;
 
-	of_property_read_u32(node, "ti,reg-size", &size);
+	of_property_read_u32(node, "ti,reg-size", &reg_size);
 
-	switch (size) {
+	switch (reg_size) {
 	case 1:
 		cb->write = crossbar_writeb;
 		break;
@@ -304,7 +304,7 @@ static int __init crossbar_of_init(struct device_node *node)
 			continue;
 
 		cb->register_offsets[i] = reserved;
-		reserved += size;
+		reserved += reg_size;
 	}
 
 	of_property_read_u32(node, "ti,irqs-safe-map", &cb->safe_map);