input: ft5x06_ts: Add debugfs entry for dump info

Add a debugfs entry to display information about controller to the user.
Also have cleared the checkpatch errors on 3.18

  This patch is propagated from 3.4 kernel
    commit: 768d5e3a47dbfddbc356f387d5825858592788f6
    input: ft5x06_ts: Add debugfs entry for dump info

Change-Id: I075501fefe1984533139ecca65af92f3c0ab8b97
Signed-off-by: Mohan Pallaka <mpallaka@codeaurora.org>
Signed-off-by: Sudhakar Manapati <smanap@codeaurora.org>