[][MAC80211][misc][preliminary version of Filogic 680 on Filogic 880]

[Description]
Add preliminary version of Filogic 680 on Filogic 880.
Based on mt76 revision: 269df4b01f27 ("wifi: mt76: fix rx checksum offload on mt7615/mt7915/mt7921")

This series adds mt7996, a new mac80211 driver for MediaTek Wi-Fi 7
(802.11be) devices, which currently supports AP, station, mesh, and
monitor modes.

mt7996 first supports Filogic 680, which is a Wi-Fi 7 chipset supporting
concurrent tri-band operation at 6 GHz, 5 GHz, and 2.4 GHz with 4x4
antennas on each band. There are several variants that will be added in
upcoming patches. For more details, please refer to [1].

mt7996 supports only Wi-Fi 6E at the moment, whereas Wi-Fi 7 and its
specific features are work in progress. They will be introduced in
further patches.

[1] https://corp.mediatek.com/news-events/press-releases/mediatek-announces-worlds-first-complete-wi-fi-7-platforms-for-access-points-and-clients

[Release-log]
N/A

Change-Id: I7d3dea2626556751c9b0462e587743fad5287be0
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/6709775
270 files changed