strace: change licenses

"The test suite is now provided under the terms of
the GNU General Public License version 2 or later."

"All the rest of strace is now provided under the terms of
the GNU Lesser General Public License version 2.1 or later."

> https://github.com/strace/strace/blob/27739ebccc96c0f70cd2aeb37fd7b0ecfef21724/NEWS#L4