The stm32l5 platforms employ a post build script, `platform/ext/target/stm/stm32l5xx/boards/scripts/postbuild.sh`, and a flash script, `platform/ext/target/stm/stm32l5xx/boards/scripts/TFM_update.sh`, working in Linux environment.
Could other environment such as OS X be supported, as it is done for the NXP LPC55S69 ? (in `platform/ext/target/nxp/lpcxpresso55s69/scripts/build.sh`). In particular for the usage of `readlink`, OS X requires `greadlink`.