Update .mailmap

I realize some of the maintainers email clients and/or scripts cannot
handle UTF-8 encoded names properly, as a result your ChangeLogs
displays me as two different person :).

Following patch adds correctly encoded name of mine into .mailmap, to
prevent appearing it not to be so or badly displayed.

Signed-off-by: S.Çağlar Onur <caglar@pardus.org.tr>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>