fingerprint: add FPC kernel driver

Adds FPC kernel driver files.

Change-Id: Ia617ab0bfe6f9b87de8021050c7d6678ab94bad9
Signed-off-by: kris_chen <kris_chen@htc.com>
Git-commit: f6a1ae75a80eae7c9f713bae17e8b1e28f5d52a5
Git-repo: https://android.googlesource.com/kernel/msm.git


[linyyuan@codeaurora.org: fix warning and improve some function]
Signed-off-by: Linyu Yuan <linyyuan@codeaurora.org>