[S390] return 'count' for successful execution of dasd_eer_enable.

Currently the return value of 'dasd_eer_enable' is returned - even if the
function returned '0'. Now return 'count' for successful execution.
Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/block/dasd_devmap.c

@@ -877,12 +877,13 @@ dasd_eer_store(struct device *dev, struct device_attribute *attr,
 	if (((endp + 1) < (buf + count)) || (val > 1))
 		return -EINVAL;
 
-	rc = count;
-	if (val)
+	if (val) {
 		rc = dasd_eer_enable(devmap->device);
-	else
+		if (rc)
+			return rc;
+	} else
 		dasd_eer_disable(devmap->device);
-	return rc;
+	return count;
 }
 
 static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);