ath79: migrate Archer C5 5GHz radio device paths
When upgrading a TP-Link Archer C5 v1 from ar71xx to ath79,
the 5ghz radio stops working because the device path changed.
Same has been done for the Archer C7 before:
commit e19506f20618 ("ath79: migrate Archer C7 5GHz radio device paths")
Signed-off-by: Jan-Niklas Burfeind <[email protected]>