ARM: imx: dynamically allocate imx2-wdt devices

Currently there is no platform data used in the driver.  In case this
changes and for consistency NULL is passed unused to the soc specific
functions.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
diff --git a/arch/arm/mach-imx/devices-imx27.h b/arch/arm/mach-imx/devices-imx27.h
index 84b3405..b2d4c51 100644
--- a/arch/arm/mach-imx/devices-imx27.h
+++ b/arch/arm/mach-imx/devices-imx27.h
@@ -13,6 +13,10 @@
 #define imx27_add_fec(pdata)	\
 	imx_add_fec(&imx27_fec_data, pdata)
 
+extern const struct imx_imx2_wdt_data imx27_imx2_wdt_data __initconst;
+#define imx27_add_imx2_wdt(pdata)	\
+	imx_add_imx2_wdt(&imx27_imx2_wdt_data)
+
 extern const struct imx_imx_i2c_data imx27_imx_i2c_data[] __initconst;
 #define imx27_add_imx_i2c(id, pdata)	\
 	imx_add_imx_i2c(&imx27_imx_i2c_data[id], pdata)