[][sync access syscfg0 safe protect]

[Description]
Fix Ethernet ping fail seldom issue when reboot from colgin.
-- syscfg0 access is not thread safe.
-- when mtk_open(eth0) and mtk_open(eth1) occur at the same time
-- Add spin_lock to protect.

[Release-log]

Change-Id: I94aae8b96ac766aef512751f6cd1f87c1db2a214
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/5597031
3 files changed