arm64: dts: renesas: r8a774a1: Remove audio port node

arm64: dts: renesas: r8a774a1: Remove audio port node

This patch removes audio port node from SoC device tree and
fixes the below dtb warning

    Warning (unit_address_vs_reg): /soc/sound@ec500000/ports/port@0: node has a unit name, but no reg property

Fixes: e2f04248fcd4 ("arm64: dts: renesas: r8a774a1: Add audio support")
Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Link: https://lore.kernel.org/r/1570200761-884-1-git-send-email-biju.das@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>