eglfs: Create mouse, keyboard and touch handlers by default

eglfs: Create mouse, keyboard and touch handlers by default

Prior to this change, input support for eglfs was loaded as plugins. With
this change, eglfs supports evdev based keyboard, mouse and touch input
out of the box.

The event dispatcher is created in the constructor because the evdev
code creates QSocketNotifiers in the constructor which requires an
event loop.

Change-Id: I4e08f4121b9381ee5b414d0886eae2b8a2925800
Reviewed-by: Johannes Zellner <johannes.zellner@nokia.com>
Reviewed-by: Romain Pokrzywka <romain.pokrzywka@kdab.com>
Reviewed-by: Donald Carr <donald.carr@nokia.com>
Reviewed-by: Girish Ramakrishnan <girish.1.ramakrishnan@nokia.com>
Reviewed-by: Laszlo Agocs <laszlo.p.agocs@nokia.com>