dt-bindings: reset: mediatek: add MT7988 ethwarp reset IDs

Add reset ID for ethwarp subsystem allowing to reset the built-in
Ethernet switch of the MediaTek MT7988 SoC.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/0c14bbacf471683af67ffa7572bfa1d5c45a0b5d.1702849494.git.daniel@makrotopia.org


Signed-off-by: Stephen Boyd <sboyd@kernel.org>