stm32/mboot: Add MBOOT_LEAVE_BOOTLOADER_VIA_RESET option.
stm32/mboot: Add MBOOT_LEAVE_BOOTLOADER_VIA_RESET option.

It is enabled by default to get the standard behaviour of doing a reset
after it is finished, but can be disabled by a board to jump straight to
the application (likely the board needs to use MBOOT_BOARD_CLEANUP to make
this work).

The application is passed a reset mode of BOARDCTRL_RESET_MODE_BOOTLOADER
if the bootloader was active and entered via a jump.

Signed-off-by: Damien George <99e6b749acbfbe2a596df99e91d24d6e1fdbee00@micropython.org>

bvernoux/micropython,adafruit/circuitpython,henriknelson/micropython,bvernoux/micropython,bvernoux/micropython,bvernoux/micropython,henriknelson/micropython,henriknelson/micropython,henriknelson/micropython,adafruit/circuitpython,bvernoux/micropython,henriknelson/micropython,adafruit/circuitpython,adafruit/circuitpython,adafruit/circuitpython,adafruit/circuitpython