commander: refactored state-machine strings
commander: refactored state-machine strings

 - Follow-up changes to https://github.com/PX4/Firmware/pull/11796
PX4/Firmware,dagar/Firmware,PX4/Firmware,krbeverx/Firmware,dagar/Firmware,dagar/Firmware,dagar/Firmware,PX4/Firmware,acfloria/Firmware,acfloria/Firmware,krbeverx/Firmware,krbeverx/Firmware,PX4/Firmware,acfloria/Firmware,PX4/Firmware,krbeverx/Firmware,PX4/Firmware,acfloria/Firmware,dagar/Firmware,dagar/Firmware,PX4/Firmware,dagar/Firmware,acfloria/Firmware,krbeverx/Firmware,acfloria/Firmware,krbeverx/Firmware,krbeverx/Firmware,acfloria/Firmware