stm32/mboot: Define constants for reset mode cycling and timeout.
stm32/mboot: Define constants for reset mode cycling and timeout.

And fix timeout value so that it does actually finish with reset_mode=1.

MrSurly/micropython,tralamazza/micropython,pramasoul/micropython,kerneltask/micropython,pramasoul/micropython,selste/micropython,adafruit/circuitpython,pfalcon/micropython,pfalcon/micropython,bvernoux/micropython,bvernoux/micropython,adafruit/circuitpython,swegener/micropython,MrSurly/micropython,MrSurly/micropython,pfalcon/micropython,pozetroninc/micropython,kerneltask/micropython,adafruit/circuitpython,pramasoul/micropython,tobbad/micropython,bvernoux/micropython,adafruit/micropython,selste/micropython,adafruit/circuitpython,adafruit/micropython,trezor/micropython,selste/micropython,henriknelson/micropython,MrSurly/micropython,bvernoux/micropython,henriknelson/micropython,pfalcon/micropython,tobbad/micropython,adafruit/circuitpython,pramasoul/micropython,swegener/micropython,pozetroninc/micropython,pramasoul/micropython,swegener/micropython,pozetroninc/micropython,pozetroninc/micropython,henriknelson/micropython,kerneltask/micropython,trezor/micropython,pfalcon/micropython,adafruit/micropython,tobbad/micropython,trezor/micropython,tobbad/micropython,tralamazza/micropython,adafruit/micropython,selste/micropython,trezor/micropython,tobbad/micropython,MrSurly/micropython,swegener/micropython,bvernoux/micropython,henriknelson/micropython,selste/micropython,kerneltask/micropython,trezor/micropython,adafruit/circuitpython,kerneltask/micropython,tralamazza/micropython,adafruit/micropython,pozetroninc/micropython,swegener/micropython,tralamazza/micropython,henriknelson/micropython