qcanobserver: Move to nonworking

* depends on qwt-5 APIs, I've tried to update it to support qwt-6 which
  is used in meta-oe, but it looks more complicated then what I've
  expected, my WIP patch is here:
  http://git.openembedded.org/meta-openembedded-contrib/log/?h=jansa/qcanobserver
  if you want to finish it and move qcanobserver back to recipes-qt
* qwt-5 was removed more then 1 year ago:
  commit 5ad3d0d0


  Author: Eric BENARD <eric@eukrea.com>
  Date:   Thu Apr 12 15:09:48 2012 +0000

    qwt: add 6.0.1 version

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>