arm64: dts: renesas: rzg2ul-smarc-som: Enable OSTM

Enable OSTM{1, 2} interfaces on RZ/G2UL SMARC EVK.
OSTM0 is reserved for TF-A.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20220425170530.200921-13-biju.das.jz@bp.renesas.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>