Match Panda DFU entry fix in "make recover" process (#509)

* Match DFU entry fix from f07a6ee in "make recover" process

* Why use many code when few code do trick

Author: jyoung8607

board/build.mk

@@ -42,7 +42,7 @@ bin: obj/$(PROJ_NAME).bin
 
 # this flashes everything
 recover: obj/bootstub.$(PROJ_NAME).bin obj/$(PROJ_NAME).bin
-	-PYTHONPATH=../ python3 -c "from python import Panda; Panda().reset(enter_bootloader=True)"
+	-PYTHONPATH=../ python3 -c "from python import Panda; Panda().reset(enter_bootstub=True); Panda().reset(enter_bootloader=True)"
 	sleep 1.0
 	$(DFU_UTIL) -d 0483:df11 -a 0 -s 0x08004000 -D obj/$(PROJ_NAME).bin
 	$(DFU_UTIL) -d 0483:df11 -a 0 -s 0x08000000:leave -D obj/bootstub.$(PROJ_NAME).bin