Input: elan_i2c - add id for touchpad found in Lenovo s21e-20

commit e154ab69 upstream.

Lenovo s21e-20 uses ELAN0601 in its ACPI tables for the Elan touchpad.

Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>