Add RSA-3072 support to MCUBoot to be aligned with PSA TBSA-M recommendation.
Related changes: https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/1126/ https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/1127/ https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/1128/