I have just fixed an IAR linking issue for the nxp/lpcxpresso55s69, see https://review.trustedfirmware.org/c/TF-M/trusted-firmware-m/+/8251
I tried using the current sources, but it seems that there is some issues causing the board to run into a hard fault when built with GNUARM.
Not sure what commit caused the breakage.
Cheers, Thomas