Kenwood, modern Yaesu rigs and many SDRs use an auto information
mechanism that broadcasts unsolicited rig state changes, Hamlib does
not support this and turns off the function. Because several passive
devices rely on this information to detect band changes for example
this change adds code to save the AI state on start up and restores it
on exit. These devices do no need the broadcasts since when an
application using Hamlib is running as necessary state polling by the
application provides continuous rig state updates.