Input: use sysfs_emit() instead of scnprintf()

Replace calls to scnprintf() in the methods showing device attributes
with sysfs_emit() to simplify the code.

Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Link: https://lore.kernel.org/r/202212021133398847947@zte.com.cn


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>