Remove this part. Previously, it was (incorrectly) documented that this should be added to local.conf, but this brought RPi out of line with all other boards, so we removed it for zeus. The reason it worked in previous branches is that the patching methods were different, and they automatically fixed this behind your back. This is no longer possible for zeus and later branches, the alignment and the patch need to match.
Note that even if you have devices that are deployed with the old setting, it is safe to upgrade them, because the setting is only used in fw_env.config, which is stored on the data partition. Hence existing devices will retain their existing alignment, even if you upgrade.