ARM: pxa: move PXA_GPIO_TO_IRQ macro

Since PXA_GPIO_TO_IRQ() & MMP_GPIO_TO_IRQ() macro are depended on
arch code, move them from gpio driver to platform driver instead.

Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/include/linux/gpio-pxa.h b/include/linux/gpio-pxa.h
index d755b28..d90ebbe 100644
--- a/include/linux/gpio-pxa.h
+++ b/include/linux/gpio-pxa.h
@@ -14,6 +14,7 @@
 extern int pxa_irq_to_gpio(int irq);
 
 struct pxa_gpio_platform_data {
+	int irq_base;
 	int (*gpio_set_wake)(unsigned int gpio, unsigned int on);
 };