input: synaptics: Add debugfs entry for dump info

Add a debugfs entry to display information about
controller to the user.

This patch is propagated from msm-3.4 kernel
(commit: d9bf0d9b2e7648dac74f0d8af04b5def1d69ff02
input: synaptics: Add debugfs entry for dump info)
Also cleaned the checkpatch warning on msm-3.18 kernel.

Change-Id: Ib358cad4bb2c81aa0194b41bc5159dffda393eeb
Signed-off-by: Amy Maloche <amaloche@codeaurora.org>
Signed-off-by: Sudhakar Manapati <smanap@codeaurora.org>