IMX UART: Add board specific init/exit functions

Add platform specific init functions. Also rename the struct
platform_device dev into pdev.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

diff --git a/include/asm-arm/arch-imx/imx-uart.h b/include/asm-arm/arch-imx/imx-uart.h
index 3a685e1..d54eb1d 100644
--- a/include/asm-arm/arch-imx/imx-uart.h
+++ b/include/asm-arm/arch-imx/imx-uart.h
@@ -4,6 +4,8 @@
 #define IMXUART_HAVE_RTSCTS (1<<0)
 
 struct imxuart_platform_data {
+	int (*init)(struct platform_device *pdev);
+	void (*exit)(struct platform_device *pdev);
 	unsigned int flags;
 };