Merge changes Ia34bc0f4,I0be3773b,I701e357a,Icdbe1992 into integration

* changes:
  refactor(versal2): guard handoff logic w/ build flag
  refactor(qemu): guard handoff logic w/ build flag
  refactor(optee): guard handoff logic w/ build flag
  feat(handoff): support libtl submodule builds