core: bootstrap: reduce aggressiveness of blueos_startup_update.py in overwriting custom pin assignments in Pi overlay

[drzwey]

Current behaviour

after editing config.txt (aka Pi overlay) with new i2c-3 assignments and reduced uart assignments, including the #custom tag, a reboot shows that the serial assignment was added. This causes a dmesg reported GPIO error.

Expected or desired behaviour

It would be nice to be able to aggressively change GPIO assignments in the overlay file. I.e. to throttle the list of desired items in the variable navigator_configs_with_match_patterns
A flag file in the system to modify the aggressiveness of this update script would be helpful. Looking at the calling script, it seems that there are many activities that are still needed, but the environment variable BLUEOS_DISABLE_STARTUP_UPDATE will prevent the entire script from running. Therefore, a more granular option is desired.

Prerequisites

• I have checked to make sure that a similar request has not already been filed or fixed.

[drzwey]

By the way, this is Mike Fair at Trident Research