nuttx px4fmu-v4 config: increase CONFIG_NFILE_DESCRIPTORS to 52
nuttx px4fmu-v4 config: increase CONFIG_NFILE_DESCRIPTORS to 52

necessary for mavlink receiver. It had the following output:
 mavlink_rcv_if0: node_open as advertiser failed.

krbeverx/Firmware,Aerotenna/Firmware,mcgill-robotics/Firmware,mje-nz/PX4-Firmware,acfloria/Firmware,dagar/Firmware,jlecoeur/Firmware,mje-nz/PX4-Firmware,jlecoeur/Firmware,PX4/Firmware,dagar/Firmware,Aerotenna/Firmware,krbeverx/Firmware,jlecoeur/Firmware,acfloria/Firmware,krbeverx/Firmware,mcgill-robotics/Firmware,mje-nz/PX4-Firmware,PX4/Firmware,PX4/Firmware,acfloria/Firmware,acfloria/Firmware,PX4/Firmware,darknight-007/Firmware,mcgill-robotics/Firmware,acfloria/Firmware,mje-nz/PX4-Firmware,krbeverx/Firmware,jlecoeur/Firmware,mje-nz/PX4-Firmware,dagar/Firmware,Aerotenna/Firmware,darknight-007/Firmware,dagar/Firmware,Aerotenna/Firmware,dagar/Firmware,PX4/Firmware,jlecoeur/Firmware,darknight-007/Firmware,mje-nz/PX4-Firmware,mje-nz/PX4-Firmware,dagar/Firmware,jlecoeur/Firmware,PX4/Firmware,PX4/Firmware,Aerotenna/Firmware,Aerotenna/Firmware,acfloria/Firmware,jlecoeur/Firmware,mcgill-robotics/Firmware,dagar/Firmware,krbeverx/Firmware,mcgill-robotics/Firmware,acfloria/Firmware,Aerotenna/Firmware,jlecoeur/Firmware,mcgill-robotics/Firmware,mcgill-robotics/Firmware,darknight-007/Firmware,krbeverx/Firmware,krbeverx/Firmware,darknight-007/Firmware