Added error message if the firmware file is not found at startup
Added error message if the firmware file is not found at startup

nfi/mspsim,cmorty/mspsim,cmorty/mspsim,contiki-os/mspsim,mspsim/mspsim,fvdnabee/mspsim,nfi/mspsim,ransford/mspsim,ransford/mspsim,mspsim/mspsim,joakimeriksson/mspsim,fvdnabee/mspsim,joakimeriksson/mspsim,contiki-os/mspsim