contrib/gitdm: add Tsukasa as an individual contributor

I wasn't sure if you want to be added as an individual contributor or
an academic so please confirm.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Tsukasa OI <research_trasio@irq.a4lg.com>
Message-Id: <20221219121914.851488-7-alex.bennee@linaro.org>
1 file changed