Update strace to 4.8:
* Update License file.
* Remove the backport patches which are already in version 4.8.
* Add file git-version-gen from git repo. Without this file configure
fails.
(From OE-Core rev: 3ae2592b40900caaebe2452c875912f82f9e5200)
Signed-off-by: Kai Kang <kai.kang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
