Revert "feat(altera): add build config and variant for Agilex3"

This reverts commit 9bc55da7dffd1d98917c7375fec5b64ce439ad0b.

Reason for revert: this change depends on the whole series from https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/35881 to be merged in TF-A.

Change-Id: I47e34a774620d28a687fb14e8f02e46f59b0c691
3 files changed