[amsat-bb] gqrx and gpredict

Hello

I found a mismatch in port numbers between gqrx and gpredict for those using SDR for ISS

gpredict is looking for port 4532

gqrx is looking for 7532

Match them

Also gqrx only works on a Mac from here the qgrx website dmg

Source code compile causes a segmentation fault

I have gpredict driving an AirSpy Mini on gqrx on a MacBook Pro

Listening for the ISS

Andrew VK4TEC

bug fixes submitted