i2c: imx: make bitrate an u32 type

sparse found this assignment of u32 to an int. Fix it:

drivers/i2c/busses/i2c-imx.c:540:56: warning: incorrect type in argument 3 (different signedness)

and also fix the type in platform_data. All current users use values
which fit into the old and new type, so it is a safe change.
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
Reviewed-by: Richard Zhao <richard.zhao@freescale.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/arm/plat-mxc/include/mach/i2c.h

@@ -15,7 +15,7 @@
  *
  **/
 struct imxi2c_platform_data {
-	int bitrate;
+	u32 bitrate;
 };
 
 #endif /* __ASM_ARCH_I2C_H_ */

drivers/i2c/busses/i2c-imx.c

@@ -471,8 +471,8 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
 	struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
 	struct pinctrl *pinctrl;
 	void __iomem *base;
-	int irq, bitrate;
-	int ret;
+	int irq, ret;
+	u32 bitrate;
 
 	dev_dbg(&pdev->dev, "<%s>\n", __func__);