MAINTAINERS: change Arınç _NAL's name and email address

My legal name now includes Chester. Change the name and the email address
sections to reflect that.

Link: https://lkml.kernel.org/r/20241225-for-unknown-upstream-v1-1-3e35e4d5e161@arinc9.com


Signed-off-by: Chester A. Unal <chester.a.unal@arinc9.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>