mailmap: add new email for davidtwco

Signed-off-by: David Wood <david@davidtw.co>

.mailmap

@@ -146,6 +146,7 @@ David Klein <david.klein@baesystemsdetica.com>
 David Manescu <david.manescu@gmail.com> <dman2626@uni.sydney.edu.au>
 David Ross <daboross@daboross.net>
 David Wood <david@davidtw.co> <david.wood@huawei.com>
+David Wood <david@davidtw.co> <david.wood2@arm.com>
 Deadbeef <ent3rm4n@gmail.com>
 Deadbeef <ent3rm4n@gmail.com> <fee1-dead-beef@protonmail.com>
 dependabot[bot] <dependabot[bot]@users.noreply.github.com> <27856297+dependabot-preview[bot]@users.noreply.github.com>