conf: Set up wic to standard image creator
conf: Set up wic to standard image creator

This patch removes the sdcard and ext tasks and adds the wic task to the
build process.

Signed-off-by: Daniel Schultz <adff8adca0fa13ca885c17ff484bfc0eae7d2508@phytec.de>
Signed-off-by: Stefan Müller-Klieser <a3e08e35e4a42be768e7d0e76ae1ba321c2a66dd@phytec.de>

PHYTEC-Messtechnik-GmbH/meta-phytec,PHYTEC-Messtechnik-GmbH/meta-phytec,PHYTEC-Messtechnik-GmbH/meta-phytec,PHYTEC-Messtechnik-GmbH/meta-phytec,PHYTEC-Messtechnik-GmbH/meta-phytec