If you run bitbake -b on something using autotools with dependencies on
m4 files, it currently fails as the TASKDEPDATA is incomplete for
bitbake -b
and this means the relevant macros aren't found.
Work around this by adding *all* m4 files for the -b case (and show a warning).
[YOCTO #8890]
(From OE-Core rev: 60207e0cf3a5bce9123d3631a10a9540c72a9034)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>