ne10: use bb.debug for debug messages

Moreover, the messages are misleading, saying "Building for arch blah",
even when this recipe is not being built. It merely checks if the recipe
is cmaptible with the currently used architecture.

Signed-off-by: Denys Dmytriyenko <denys@ti.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>