If you have an existing Vitis-compatible Vivado IP and need to generate the XO file from it, you could also manually create the kernel XML file, and designate it in the command as follows:
package_xo -xo_path ../krnl_cbc.xo -kernel_name krnl_cbc -ip_directory ./krnl_cbc_ip -kernel_xml ../krnl_cbc.xml
In this case, the kernel execution model is specified in the XML file with hwControlProtocol property instead of in the package_xo command line option.