ab8500_btemp: Harden platform data check

If no platform data at all is supplied the driver crashes,
extend the checks to be more careful so we can compile in the
driver and boot also without platform data present.

Acked-by: Arun Murthy <arun.murthy@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>

drivers/power/ab8500_btemp.c

@@ -978,12 +978,12 @@ static int __devinit ab8500_btemp_probe(struct platform_device *pdev)
 
 	/* get btemp specific platform data */
 	plat_data = pdev->dev.platform_data;
-	di->pdata = plat_data->btemp;
-	if (!di->pdata) {
+	if (!plat_data || !plat_data->btemp) {
 		dev_err(di->dev, "no btemp platform data supplied\n");
 		ret = -EINVAL;
 		goto free_device_info;
 	}
+	di->pdata = plat_data->btemp;
 
 	/* get battery specific platform data */
 	di->bat = plat_data->battery;