powerpc: Rework ipic_init() so we can avoid freeing the irq_host

If we do the call to of_address_to_resource() first, then we don't
need to worry about freeing the irq_host (which the code doesn't do
currently anyway).
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

arch/powerpc/sysdev/ipic.c

@@ -725,6 +725,10 @@ struct ipic * __init ipic_init(struct device_node *node, unsigned int flags)
 	struct resource res;
 	u32 temp = 0, ret;
 
+	ret = of_address_to_resource(node, 0, &res);
+	if (ret)
+		return NULL;
+
 	ipic = alloc_bootmem(sizeof(struct ipic));
 	if (ipic == NULL)
 		return NULL;
@@ -739,12 +743,6 @@ struct ipic * __init ipic_init(struct device_node *node, unsigned int flags)
 		return NULL;
 	}
 
-	ret = of_address_to_resource(node, 0, &res);
-	if (ret) {
-		of_node_put(node);
-		return NULL;
-	}
-
 	ipic->regs = ioremap(res.start, res.end - res.start + 1);
 
 	ipic->irqhost->host_data = ipic;