The recent change to verify_checksum() to only show checksum warnings
if no checksums are supplied made it possible to simplify the logic a
bit more.
(Bitbake rev: 1dc00b874acae44bbba9d8028d94f7bc97ddcd76)
Signed-off-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>