setting up a DEFAULTGPIO pulldown in bootloaders is a bad idea as it
overrides any hardware pullups that have been put in place as part of
a "hold in bootloader" mechanism. See discussion in #27360 for ELRS
note that this only impacts one board that I can see, the
BlitzF745AIO, due to the MCU vs DEFAULTGPIO interaction
we can tell these are incorrect as they init to LOW, and previously we
didn't have handling of VDD_5V_PERIPH_EN, so we know that LOW is
enabled or the boards would not have worked
this fixes GPS on Pixhawk1