fmp4mux: add support for MISB KLV metadata
MISB ST1910 specifies how to package metadata into an Event Message (emsg) Box of the CMAF. meta/x-klv could be added as a type accepted on the sink pad.
MISB ST1910 specifies how to package metadata into an Event Message (emsg) Box of the CMAF. meta/x-klv could be added as a type accepted on the sink pad.