[][openwrt][common][bsp][Add support to reset boot count of dual image booting]

[Description]
Add built-in kernel driver to allow resetting boot count of A/B systems
Add init script which will be executed after init done.

[Release-log]
N/A

Change-Id: I9aeecccc6f7ffa34b69530041aeb0585eb6d6929
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/8823085
5 files changed