input: touchscreen: Add focaltech FT3267 touchscreen driver

Ft32x7 controllers are single chip capacitive
touch panel controller ICs with Micro Controller Unit.
It supports multi-touch capability and can detect
up to five touches.

This version (V1.3_20170306) also supports ICs
FT3207, FT3267, FT5822, FT5x46, FT6336G/U,
FT8006, FT8606, FT8607, FT8716, FT8736.

Fix checkpatch errors, add dts documentation,
change wakelocks to corresponding pm_* calls
and change file open calls to firmware_class calls.

Change-Id: If33025b1c292f39e8b059e6247cbbb547ab942d2
Signed-off-by: Venkata Prahlad Valluru <vvalluru@codeaurora.org>