net: mtk_eth_soc: enable flow offload support for MT7986 SoC

Since Wireless Ethernet Dispatcher is now available for mt7986 in mt76,
enable hw flow support for MT7986 SoC.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/fdcaacd827938e6a8c4aa1ac2c13e46d2c08c821.1670072898.git.lorenzo@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>