arm64: defconfig: Regenerate for v4.20

Run the platform defconfig through kbuild, and handle the trivial case
where options merely move around.

Signed-off-by: Marc Gonzalez <marc.w.gonzalez@free.fr>
[olof: refreshed due to some recent churn]
Signed-off-by: Olof Johansson <olof@lixom.net>

Signed-off-by: Olof Johansson <olof@lixom.net>