uboot-mediatek: refresh device defconfig files

uboot-mediatek: refresh device defconfig files

It seems that most of them are manually modified. However, we can
use `make savedefconfig` to generate a clean defconfig file.

Refreshed by:
```
Boards=(
	mt7623n_bpir2_defconfig \
	mt7623a_unielec_u7623_02_defconfig \
	mt7622_bananapi_bpi-r64-sdmmc_defconfig \
	mt7622_bananapi_bpi-r64-emmc_defconfig \
	mt7622_bananapi_bpi-r64-snand_defconfig \
	mt7622_linksys_e8450_defconfig \
	mt7622_ubnt_unifi-6-lr-v1_defconfig \
	mt7622_ubnt_unifi-6-lr-v2_defconfig \
	mt7622_ubnt_unifi-6-lr-v3_defconfig \
	ravpower-rp-wd009-ram_defconfig \
	mt7621_zbtlink_zbt-wg3526-16m_defconfig \
	mt7986_netcore_n60_defconfig \
	mt7986a_bpi-r3-emmc_defconfig \
	mt7986a_bpi-r3-nor_defconfig \
	mt7986a_bpi-r3-sd_defconfig \
	mt7986a_bpi-r3-snand_defconfig \
	mt7986_xiaomi_redmi-ax6000_defconfig \
	mt7986_tplink_tl-xdr4288_defconfig \
	mt7986_tplink_tl-xdr6086_defconfig \
	mt7986_tplink_tl-xdr6088_defconfig \
	mt7981_qihoo-360t7_defconfig \
	mt7981_xiaomi_mi-router-wr30u_defconfig \
	mt7981_h3c_magic-nx30-pro_defconfig \
	mt7986a_glinet_gl-mt6000_defconfig \
	mt7981_cmcc_rax3000m-emmc_defconfig \
	mt7981_cmcc_rax3000m-nand_defconfig \
	mt7981_jcg_q30-pro_defconfig \
	mt7986_zyxel_ex5601-t0_defconfig \
	mt7981_xiaomi_mi-router-ax3000t_defconfig \
	mt7986a_jdcloud_re-cp-03_defconfig \
	mt7986a_bpi-r3-mini-emmc_defconfig \
	mt7986a_bpi-r3-mini-snand_defconfig \
	mt7981_nokia_ea0326gmp_defconfig \
	mt7988a_bananapi_bpi-r4-emmc_defconfig \
	mt7988a_bananapi_bpi-r4-sdmmc_defconfig \
	mt7988a_bananapi_bpi-r4-snand_defconfig \
	mt7988a_bananapi_bpi-r4-poe-emmc_defconfig \
	mt7988a_bananapi_bpi-r4-poe-sdmmc_defconfig \
	mt7988a_bananapi_bpi-r4-poe-snand_defconfig \
	mt7622_xiaomi_redmi-router-ax6s-ubi-loader_defconfig \
	mt7981_openwrt-one-nor_defconfig \
	mt7981_openwrt-one-spi-nand_defconfig \
	)

for Board in ${Boards[@]}
do
	echo "Refresh board ${Board}"
	make ${Board}
	make savedefconfig
	cat ./defconfig > ./configs/${Board}
done
```

Signed-off-by: Shiji Yang <yangshiji66@qq.com>