Revert "dt2w: improve accuracy of single touch detection"

This reverts commit 82a6514c66c50638c3cfcb67743df50b85d65336.
input: touchscreen: refactoring dt2w code

Refactoring the dt2w code by applying mainline code
style guidelines. Although this changes a lot by
moving some stuff into the header it should have no
actual functional change.
The very only change i did is using power efficient
workqueues instead of the cpu-bound one to prevent
battery drain a bit.

Signed-off-by: Blechd0se <alex.christ@hotmail.de>

Fixed some cherry-picking errors caused by my previous "from early to powersuspend" commit.
Conflicts:
	drivers/input/touchscreen/doubletap2wake.c
	drivers/input/touchscreen/sweep2wake.c