boards: AeroFC: Make it a memory constrained system
boards: AeroFC: Make it a memory constrained system

The maximum number of missions was increased in almost 8 times in
recent commit: 9369262e63 navigator: allow more mission items.

As this board loads missions in RAM, now it don't have enough memory
to allocate causing dataman start to fail, so mark it as a memory
constrained system and reduce the number of maximum missions
supported.

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