mailmap: update email address for Alex Shi

mailmap: update email address for Alex Shi

Add my kernel.org address for old email address.

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Alexander Lobakin <alobakin@pm.me>
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1616748571-52058-1-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>