watchdog: bcm7038: Check the return value from clk_prepare_enable()

clk_prepare_enable() may fail, so we should better check its return value
and propagate it in the case of error.

Signed-off-by: Fabio Estevam <[e-mail]>
Reviewed-by: Guenter Roeck <[e-mail]>
Signed-off-by: Guenter Roeck <[e-mail]>
Signed-off-by: Wim Van Sebroeck <[e-mail]>

drivers/watchdog/bcm7038_wdt.c

···
 	wdt->clk = devm_clk_get(dev, NULL);
 	/* If unable to get clock, use default frequency */
 	if (!IS_ERR(wdt->clk)) {
-		clk_prepare_enable(wdt->clk);
+		err = clk_prepare_enable(wdt->clk);
+		if (err)
+			return err;
 		wdt->rate = clk_get_rate(wdt->clk);
 		/* Prevent divide-by-zero exception */
 		if (!wdt->rate)