Building bare-metal applications requires a bare-metal domain in the platform. In Module 01, you created a custom platform with a bare-metal domain. In Module 04, you built on top of your custom platform and added PL kernels (and subsequently their PS drivers) to the design. The first step of building the bare-metal PS host application is to use the XSA generated during the link process to create a new software platform using the following command.
generate-platform.sh -name vck190_baremetal \
-hw ../../Module_04_AI_Engine_and_PL_Integration/build/rev1/hw/beamforming.rev1.hw.xsa \
-domain ai_engine:aie_runtime \
-domain psv_cortexa72_0:standalone \
-out-dir build
The options are explained in the AI Engine Documentation: Building a Bare-Metal System.