[][kernel][mt7988][eth][Update 1000basex support and refactor to upstream style for the SGMII]

Refactor SGMII reset flow for the NETSYSv3.

Only reset and setup PCS/PHYA of the NETSYSv3 when the interface changed.

Current support types:
    - 1000BASEX wo autoneg
    - SGMII w autoneg
    - HSGMII wo autoneg

If without this patch, the kernel might misconfiguration SGMII speed
and polarity when down/up interface.


Change-Id: Ie255934ec65f8ddc511c99713e53e2a4cd810394
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7440863
1 file changed