mmc: block: add newline to sysfs display of force_ro

commit 0031a98a upstream.

Make force_ro consistent with other sysfs entries.

Fixes: 371a689f ('mmc: MMC boot partitions support')
Cc: Andrei Warkentin <andrey.warkentin@gmail.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

drivers/mmc/card/block.c

@@ -260,7 +260,7 @@ static ssize_t force_ro_show(struct device *dev, struct device_attribute *attr,
 	int ret;
 	struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
 
-	ret = snprintf(buf, PAGE_SIZE, "%d",
+	ret = snprintf(buf, PAGE_SIZE, "%d\n",
 		       get_disk_ro(dev_to_disk(dev)) ^
 		       md->read_only);
 	mmc_blk_put(md);