It is possible for a submodule to be defined in the .gitmodules file, but
never initialized in the repository itself. This shows itself when searching
for the defined module hash you will get back a empty value.
Similarly we need to identify and skip defined but not initialized submodules
during the unpack stages as well.
Thanks to raphael.lisicki@siemens.com for their help is figuring out how
to resolve this issue.
Additionally a problem was found where, while unlikely, it may be possible
for the wrong revision to have been searched using ls-tree. This has been
resolved in the update_submodules function by keeping the correct revision
along with the submodule path.
(Bitbake rev: 49e1ff920143dcd4e7f73933d7ab8a84b8ffa1a3)
Signed-off-by: Mark Hatle <mark.hatle@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>