net: ethernet: mtk_eth_soc: add version in mtk_soc_data

Introduce version field in mtk_soc_data data structure in order to
make mtk_eth driver easier to maintain for chipset configuration
codebase. Get rid of MTK_NETSYS_V2 bit in chip capabilities.
This is a preliminary patch to introduce support for MT7988 SoC.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Link: https://lore.kernel.org/r/e52fae302ca135436e5cdd26d38d87be2da63055.1690246066.git.daniel@makrotopia.org


Signed-off-by: Jakub Kicinski <kuba@kernel.org>