ARM: pxa: rename IRQ_GPIO to PXA_GPIO_TO_IRQ

Avoid potential naming confliction since multiple architecture will be built
in a single kernel.

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/arch/arm/mach-pxa/mainstone.c b/arch/arm/mach-pxa/mainstone.c
index 0567d39..ea62a99 100644
--- a/arch/arm/mach-pxa/mainstone.c
+++ b/arch/arm/mach-pxa/mainstone.c
@@ -178,8 +178,8 @@
 	MST_INTMSKENA = 0;
 	MST_INTSETCLR = 0;
 
-	irq_set_chained_handler(IRQ_GPIO(0), mainstone_irq_handler);
-	irq_set_irq_type(IRQ_GPIO(0), IRQ_TYPE_EDGE_FALLING);
+	irq_set_chained_handler(PXA_GPIO_TO_IRQ(0), mainstone_irq_handler);
+	irq_set_irq_type(PXA_GPIO_TO_IRQ(0), IRQ_TYPE_EDGE_FALLING);
 }
 
 #ifdef CONFIG_PM