Currently the INCOMPATIBLE_LICENSE check is exact against a given license term, this should be modified to map between SPDX and old style as we move toward more SPDX license fields.
Fixed by: http://git.yoctoproject.org/cgit/cgit.cgi/poky-contrib/commit/?h=eflanagan/incompatible_license&id=a455f24986a67550a5495cc77d7073e044c7499f
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