[][MAC80211][WiFi6][mt76][Add support for IEEE 802.11 fragmentation]

[Description]
Add fragmentation index into TXD.DW2 to support IEEE 802.11 fragmentation.

[Release-log]
N/A

Change-Id: Ibf2a1f40f597d124e97ae737d95c2874705a081b
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/8898121
1 file changed