hwmon: Fix unchecked return status, batch 1

Fix up some hwmon drivers so that they no longer ignore return status
from device_create_file().
Signed-off-by: NMark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>