This massively cleans up the dependency handling in the two classes
when interacting with BBCLASSEXTEND.
This change has a dependency on the bitbake override handling change
and also the existence of the RecipePreFinalise event.
(From OE-Core rev: f183c7cfe377fa6ed2777605c3590a9dda2060df)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>