staging: nvec: Add myself to copyright and authors list

Forgotten in the last commit(s) which contained the copyrightable
material, so let's add it now. I believe that only my nvec.c
contributions are copyrightable, nvec.h is just interface naming,
so does not deserve that yet.

Signed-off-by: Julian Andres Klode <jak@jak-linux.org>
Acked-by: Marc Dietrich <marvin24@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>