[][MAC80211][misc][update mt76 Makefile patch]

[Description]
Add testmode firmwares into Makefile patch and remove the splitted patch
file.

[Release-log]
N/A

Change-Id: I25d8fed6f6e33b4fea536aac7b954ef9f011456e
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7519525
3 files changed