Revert "mailmap: Update philmd email address"

This mailmap entry does not work as I expected. I am receiving
emails related to my hobbyist contributions in my work mailbox
and I get distracted :) Remove the entry to keep things separated.

This reverts commit 28937123.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200806135832.2319-1-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>