powerpc: Fix irq_alloc_host() reference counting and callers

When I changed irq_alloc_host() to take an of_node
(52964f87c64e6c6ea671b5bf3030fb1494090a48: "Add an optional
device_node pointer to the irq_host"), I botched the reference
counting semantics.

Stephen pointed out that it's irq_alloc_host()'s business if
it needs to take an additional reference to the device_node,
the caller shouldn't need to care.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/sysdev/uic.c b/arch/powerpc/sysdev/uic.c
index 625b275..d35405c 100644
--- a/arch/powerpc/sysdev/uic.c
+++ b/arch/powerpc/sysdev/uic.c
@@ -280,12 +280,10 @@
 	}
 	uic->dcrbase = *dcrreg;
 
-	uic->irqhost = irq_alloc_host(of_node_get(node), IRQ_HOST_MAP_LINEAR,
+	uic->irqhost = irq_alloc_host(node, IRQ_HOST_MAP_LINEAR,
 				      NR_UIC_INTS, &uic_host_ops, -1);
-	if (! uic->irqhost) {
-		of_node_put(node);
+	if (! uic->irqhost)
 		return NULL; /* FIXME: panic? */
-	}
 
 	uic->irqhost->host_data = uic;