[rdkb][common][bsp][Refactor and sync kernel from openwrt]

[Description]
6427cab [MAC80211][app][Update smp.sh for eth2]
87b6df6 [MAC80211][infra][Update dts for mt76 to support flash mode]
98ac6c0 [kernel][common][eth][Add phy state sanity check to heartbeat thread for Aquantia firwmare download]

[Release-log]

Change-Id: Ia4c8cfb59a43343a6b4f2d32e7b57b3c8ef44f50
8 files changed