Add support for AVM FRITZ!Box 5530

it would be nice to have OpenWrt on this fritzbox 5530

Somewhere between unlikely (at least considering its main features) and a long road with an unclear ending ahead.!Box_5530_Fiber

Woohoo! PRX300 based. That's the MIPS based 3rd generation SoC from Intel's former Home Gateway Platform Division which they sold off to MaxLinear a few years back. Haven't actually seen many real devices with those.

There is actually a whole thread about the abandonment of that MIPS InterAptiv stuff...