watchdog: imx: use clk_get to acquire the watchdog clock

Use clk_get to acquire the watchdog clock and also avoid hardcoding the clock name.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/mach-mx3/clock-imx31.c b/arch/arm/mach-mx3/clock-imx31.c
index 7cf6d29..4193cf5 100644
--- a/arch/arm/mach-mx3/clock-imx31.c
+++ b/arch/arm/mach-mx3/clock-imx31.c
@@ -530,7 +530,7 @@
 	_REGISTER_CLOCK("imx31-cspi.2", NULL, cspi3_clk)
 	_REGISTER_CLOCK(NULL, "gpt", gpt_clk)
 	_REGISTER_CLOCK(NULL, "pwm", pwm_clk)
-	_REGISTER_CLOCK("imx-wdt.0", NULL, wdog_clk)
+	_REGISTER_CLOCK("imx2-wdt.0", NULL, wdog_clk)
 	_REGISTER_CLOCK(NULL, "rtc", rtc_clk)
 	_REGISTER_CLOCK(NULL, "epit", epit1_clk)
 	_REGISTER_CLOCK(NULL, "epit", epit2_clk)