If we "bitbake X -c packagedata" and the packagedata comes from sstate, we
don't need any of the tasks dependencies. This is similar to the
populate_lic case, we only care about the end result.
Therefore short circuit the dependencies so packagedata doesn't pull in
any other dependencies.
(From OE-Core rev: 76aa4f49db7d32bbd35703c64470fdfc63f403a4)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>