Input: synaptics-rmi4 - convert to use sysfs_emit() APIs

Follow the advice of the Documentation/filesystems/sysfs.rst and show()
should only use sysfs_emit() or sysfs_emit_at() when formatting the value
to be returned to user space.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: zhang songyi <zhang.songyi@zte.com.cn>
Link: https://lore.kernel.org/r/20220927070936.258300-1-zhang.songyi@zte.com.cn


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