hwmon: (ina2xx) Convert sysfs sprintf/snprintf family to sysfs_emit

hwmon: (ina2xx) Convert sysfs sprintf/snprintf family to sysfs_emit

Fix the following coccicheck warning:

drivers/hwmon/ina2xx.c:313:8-16: WARNING: use scnprintf or sprintf
drivers/hwmon/ina2xx.c:453:8-16: WARNING: use scnprintf or sprintf
drivers/hwmon/ina2xx.c:484:8-16: WARNING: use scnprintf or sprintf
drivers/hwmon/ina2xx.c:540:8-16: WARNING: use scnprintf or sprintf

Signed-off-by: Zihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: Jay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1615892457-35501-1-git-send-email-f.fangjian@huawei.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>