[][kernel][mt7988][pinctrl][Fix pin number assignment]

[Description]
Fix wrong i2c pin number assignment in pinctrl driver
Use correct gpio pin number 84 instead of 83

[Release-log]
N/A


Change-Id: I7e0e50a96a846f408198fb5871d294f240535e31
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7608761
2 files changed