Add R8A77965 M3N Salvator-XS development kit support. This kit is similar to the other Salvator-X(S) ones, except is has M3N SoC on it. Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com> Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>