Add startup's obj file remove action in the Makefile
Add startup's obj file remove action in the Makefile

UrsusPilot/firmware,shengwen1997/moonbear-firmware,ming6842/firmware,zxc2694/moonbear-firmware,ming6842/firmware,UrsusPilot/firmware,zxc2694/moonbear-firmware,fboris/firmware,UrsusPilot/firmware,shengwen1997/moonbear-firmware,ming6842/firmware,ming6842/firmware-new,fboris/firmware,ming6842/firmware-new,ming6842/firmware-new,shengwen1997/moonbear-firmware,zxc2694/moonbear-firmware,fboris/firmware