[ARM] MXC: remove dependency to other include files from irqs.h

This patch removes the inclusion of mach/hardware.h from mach/irqs.h and
switches to more meaningful names for the irq related macros.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/plat-mxc/include/mach/gpio.h b/arch/arm/plat-mxc/include/mach/gpio.h
index 65eedc0..ea509f1 100644
--- a/arch/arm/plat-mxc/include/mach/gpio.h
+++ b/arch/arm/plat-mxc/include/mach/gpio.h
@@ -27,8 +27,8 @@
 #define gpio_set_value		__gpio_set_value
 #define gpio_cansleep		__gpio_cansleep
 
-#define gpio_to_irq(gpio)	(MXC_MAX_INT_LINES + (gpio))
-#define irq_to_gpio(irq)	((irq) - MXC_MAX_INT_LINES)
+#define gpio_to_irq(gpio)	(MXC_GPIO_IRQ_START + (gpio))
+#define irq_to_gpio(irq)	((irq) - MXC_GPIO_IRQ_START)
 
 struct mxc_gpio_port {
 	void __iomem *base;