igt-gpu-tools: do not write shortened git commit hash into binaries

igt-gpu-tools: do not write shortened git commit hash into binaries

Shortened hashes are prone to collisions, and in this case git
lengthens the hash to resolve the collision. This in turn breaks
reproducibility, depending on whether the colliding hash is present
in the history or not. This has been observed here:
http://autobuilder.yocto.io/pub/repro-fail/oe-reproducible-20230917-br60if6q/packages/diff-html/

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit a74e1eff93d4de5724481e3298308a6d925a4512)
Signed-off-by: Steve Sakoman <steve@sakoman.com>