Update get_possible_traffic_source_addresses returned array format
Update get_possible_traffic_source_addresses returned array format

With this change it looks to me like the way it is intended to be, based
on what was done to get_possible_listen_ips()
Please review and check if this is what was intended for the code. With
this change it should make the returned $sourceips array be in a
consistent format the same way as get_possible_listen_ips()
This is a fix for code that was only committed in master. So at this
time the fix is only needed in master.

ptorsten/pfsense,ptorsten/pfsense,NewEraCracker/pfsense,phil-davis/pfsense,NewEraCracker/pfsense,dennypage/pfsense,phil-davis/pfsense,BlackstarGroup/pfsense,NOYB/pfsense,dennypage/pfsense,dennypage/pfsense,ch1c4um/pfsense,brunostein/pfsense,BlackstarGroup/pfsense,BlackstarGroup/pfsense,pfsense/pfsense,ch1c4um/pfsense,ptorsten/pfsense,brunostein/pfsense,phil-davis/pfsense,NewEraCracker/pfsense,dennypage/pfsense,pfsense/pfsense,jxmx/pfsense,pfsense/pfsense,phil-davis/pfsense,NewEraCracker/pfsense,ch1c4um/pfsense,ch1c4um/pfsense,NOYB/pfsense,NOYB/pfsense,BlackstarGroup/pfsense,brunostein/pfsense,jxmx/pfsense,pfsense/pfsense,jxmx/pfsense