[][MAC80211][wifi7][core][remove antenna_gain patch]

[Description]
Remove the revert patch of configuring antenna gain support since it's
removed from openwrt master.

[Release-log]
N/A

Change-Id: I656f8cb8df76c06a112a212ae413a4145cf9267d
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7965377
1 file changed