[wireless-regdb] wireless-regdb: Update regulatory rules for South Africa (ZA) on 5GHz

[Johannes Berg]

> The bands don’t quite match up and DFS/TPC is (apparently) not 
> required for 5470 - 5725. More importantly, the max transmitted power
> seems to be 1W/30dBm e.i.r.p and not 27dBm.

Without checking now, just a note: we sometimes have lower limits here
due to spectral power density, indoor/outdoor or TPC requirements.

johannes