of/irq: Use irq_of_parse_and_map()

Replace some instances of of_irq_map_one()/irq_create_of_mapping() and
of_irq_to_resource() by the simpler equivalent irq_of_parse_and_map().

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
[grant.likely: resolved conflicts with core code renames]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
diff --git a/arch/powerpc/sysdev/mpic_msgr.c b/arch/powerpc/sysdev/mpic_msgr.c
index c753258..2c9b52a 100644
--- a/arch/powerpc/sysdev/mpic_msgr.c
+++ b/arch/powerpc/sysdev/mpic_msgr.c
@@ -237,15 +237,13 @@
 		raw_spin_lock_init(&msgr->lock);
 
 		if (receive_mask & (1 << i)) {
-			struct resource irq;
-
-			if (of_irq_to_resource(np, irq_index, &irq) == NO_IRQ) {
+			msgr->irq = irq_of_parse_and_map(np, irq_index);
+			if (msgr->irq == NO_IRQ) {
 				dev_err(&dev->dev,
 						"Missing interrupt specifier");
 				kfree(msgr);
 				return -EFAULT;
 			}
-			msgr->irq = irq.start;
 			irq_index += 1;
 		} else {
 			msgr->irq = NO_IRQ;