ELAN0611 touchpad uses elan_i2c as its driver. It can be found
on Lenovo ideapad 320-15IKB.

So add it to ACPI table to enable the touchpad.

[Ido Adiv <idoad123@gmail.com> reports that the same ACPI ID is used for
Elan touchpad in ideapad 520].

BugLink: https://bugs.launchpad.net/bugs/1723736Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>