kbdlogger: code cleanup

Change-Id: I0d168ff86091d94ee11c40008c89ca2a51002c93
kbdlogger: Created a struct to geather the event driver data

The struct kbdloggerdev holds the keylogger (event) driver information.
Only the already working code was included. Further development for the
other funcions is  necessary.

Change-Id: I760245f8d8ad7daf9e40744b162a42f76083b06e