HID: usbhid: enable always-poll quirk for Elan Touchscreen

Enable the always-poll quirk for Elan Touchscreens found on some recent
Samsung laptops.

Without this quirk the device keeps disconnecting from the bus (and is
re-enumerated) unless opened (and kept open, should an input event
occur).

Note that while the device can be run-time suspended, the autosuspend
timeout must be high enough to allow the device to be polled at least
once before being suspended. Specifically, using autosuspend_delay_ms=0
will still cause the device to disconnect on input events.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>