input: ft5x06_ts: Add DT support

Add device tree support for focaltech controller driver.
The data is represented in device tree format and parsed
by the driver using of framework apis.

This patch is a propagated patch from 3.18 kernel
'commit 83310a9a151e ("input: ft5x06_ts: Add DT support")'

Change-Id: Ibcdd8c3579f401ac0632d670e1b7c674aa67ba8d
Signed-off-by: Mohan Pallaka <mpallaka@codeaurora.org>
Signed-off-by: Shantanu Jain <shjain@codeaurora.org>
[abinayap@codeaurora.org: Fix checkpatch errors for 4.4 kernel
struct of_device_id should normally be const]
Signed-off-by: Abinaya P <abinayap@codeaurora.org>