sparc: Restore irq_trans_init() call in prom_create_node().

This broke sparc64 in various ways.

Add an empty dummy hook in sparc32's prom_32.c so that we
can potentially handle things on that side similarly, and
in particular avoid a prom_common.c ifdef :-)

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/kernel/prom_common.c

@@ -243,10 +243,10 @@ static struct device_node * __init prom_create_node(phandle node,
 	dp->type = get_one_property(node, "device_type");
 	dp->node = node;
 
-	/* Build interrupts later... */
-
 	dp->properties = build_prop_list(node);
 
+	irq_trans_init(dp);
+
 	return dp;
 }