skales: remove dtbTool
skales: remove dtbTool

it is no longer being used. while making this change also remove wrong
dependencies from DEPENDS.

Signed-off-by: Nicolas Dechesne <05fca36dfcf68f7e1c9eaf62b074676ab50a133b@linaro.org>

ndechesne/meta-qcom,ndechesne/meta-qcom,ndechesne/meta-qcom,ndechesne/meta-qualcomm