increase the UART buffer sizes to 256
increase the UART buffer sizes to 256

The most critical one is the GPS serial port receive buffer size,
which needs to be at least 128 to support the UBLOX protocol, but it
seems a good idea for people running a FMU without a IO board to
increase the UART buffer sizes generally

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