arm64: dts: renesas: r8a774b1-hihope-rzg2n: Enable HS400 mode

This patch enables HS400 mode on HiHope RZ/G2N board.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Link: https://lore.kernel.org/r/1569837778-55874-1-git-send-email-biju.das@bp.renesas.com


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