spdx30_tasks: Change package license to declared

spdx30_tasks: Change package license to declared

Per discussion with SPDX licensing group, the package license statements
classify as declared licenses, not concluded licenses.

Note that this is the same as a change made to the recipe licenses, just
for packages.

Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>