mailmap: fix Kishon's email

Kishon updated his email in commit e6aa4edd ("MAINTAINERS: Update
Kishon's email address in PCI endpoint subsystem").

However, as he is no longer at TI, his TI email now bounces.

Add the same email as he has in MAINTAINERS to a mailmap, so that
get_maintainer.pl will not output an email that bounces.

(This is neeed as get_maintainer.pl will use "git author" to CC
people who have significantly modified the same file as you.)

Link: https://lkml.kernel.org/r/20240229134318.1201935-1-cassel@kernel.org


Signed-off-by: Niklas Cassel <cassel@kernel.org>
Cc: Kishon Vijay Abraham I <kishon@kernel.org>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>