[streamers/MIB] added new registers for fixed-latency streamers

new registers were added to diag/snmp outputs from wr-streamers.
The MIB is now expanded accordingly. The version was not bumped
to maintain backward compatibility. The new variables are added
at the end.
Status Job ID Name Coverage
  Make Wrpc Sw
canceled #12829

  Make Rt Cpu
canceled #12830