fmu-v5 board_config: add FMU_CH7 and FMU_CH8
fmu-v5 board_config: add FMU_CH7 and FMU_CH8

mcgill-robotics/Firmware,krbeverx/Firmware,PX4/Firmware,acfloria/Firmware,mje-nz/PX4-Firmware,Aerotenna/Firmware,acfloria/Firmware,mje-nz/PX4-Firmware,acfloria/Firmware,jlecoeur/Firmware,dagar/Firmware,mcgill-robotics/Firmware,dagar/Firmware,PX4/Firmware,krbeverx/Firmware,mje-nz/PX4-Firmware,Aerotenna/Firmware,krbeverx/Firmware,jlecoeur/Firmware,PX4/Firmware,krbeverx/Firmware,Aerotenna/Firmware,Aerotenna/Firmware,mje-nz/PX4-Firmware,jlecoeur/Firmware,mcgill-robotics/Firmware,jlecoeur/Firmware,acfloria/Firmware,Aerotenna/Firmware,mcgill-robotics/Firmware,dagar/Firmware,krbeverx/Firmware,PX4/Firmware,jlecoeur/Firmware,acfloria/Firmware,mcgill-robotics/Firmware,jlecoeur/Firmware,PX4/Firmware,krbeverx/Firmware,mje-nz/PX4-Firmware,dagar/Firmware,mje-nz/PX4-Firmware,krbeverx/Firmware,mcgill-robotics/Firmware,acfloria/Firmware,mje-nz/PX4-Firmware,Aerotenna/Firmware,PX4/Firmware,jlecoeur/Firmware,PX4/Firmware,dagar/Firmware,mcgill-robotics/Firmware,acfloria/Firmware,jlecoeur/Firmware,dagar/Firmware,Aerotenna/Firmware,dagar/Firmware