BSW_EFSSecondary: rm stale p4-sdp/p4 dir before install_sdp.sh
Without DANGER_CLEAN, the /opt/perforce/p4-sdp/p4 dir from the AMI persists,
causing install_sdp.sh to fail at mkdir. Remove it before running install_sdp.sh
so it can properly create the directory with the right ServerType structure.