mailmap, MAINTAINERS: move to tycho.pizza

I've changed my e-mail address to tycho.pizza, so let's reflect that in
these files.

Signed-off-by: Tycho Andersen <tycho@tycho.pizza>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200902014017.934315-2-tycho@tycho.pizza


Signed-off-by: Kees Cook <keescook@chromium.org>