After a recent commit the rule for fPIE was removed and supposedly replaced with flag "ENABLE_PIE" but it can not be found. commit hash: 467836357943f3a08a2ee3686e2878c51f9c4453
By mistake I copied another commit hash. This is the mentioned commit hash: 1061ed6c6273e90618b05ddc0cb66be17364da33
You need to set the configuration option BR2_TARGET_ARM_TRUSTED_FIRMWARE_ADDITIONAL_VARIABLES to ENABLE_PIE=1. Closing this issue under the assumption that that helps. If not, please reopen.