ARM: imx: eliminate macro IMX_GPIO_TO_IRQ()

This patch changes all the static gpio irq number assigning with
IMX_GPIO_TO_IRQ() to run-time assigning with gpio_to_irq call, and
in turn eliminates the macro IMX_GPIO_TO_IRQ().

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/mach-imx/mach-cpuimx51sd.c b/arch/arm/mach-imx/mach-cpuimx51sd.c
index ac50f16..e42c6f8 100644
--- a/arch/arm/mach-imx/mach-cpuimx51sd.c
+++ b/arch/arm/mach-imx/mach-cpuimx51sd.c
@@ -259,7 +259,7 @@
 		.mode		= SPI_MODE_0,
 		.chip_select     = 0,
 		.platform_data   = &mcp251x_info,
-		.irq             = IMX_GPIO_TO_IRQ(CAN_IRQGPIO)
+		/* irq number is run-time assigned */
 	},
 };
 
@@ -310,6 +310,7 @@
 	msleep(20);
 	gpio_set_value(CAN_RST, 1);
 	imx51_add_ecspi(0, &cpuimx51sd_ecspi1_pdata);
+	cpuimx51sd_spi_device[0].irq = gpio_to_irq(CAN_IRQGPIO);
 	spi_register_board_info(cpuimx51sd_spi_device,
 				ARRAY_SIZE(cpuimx51sd_spi_device));