The string used to fill in the remote ID suboption.
If the value of hh3cDhcpSnoop2IfVlanRIDMode is NOT 'userDefine',
this object is set with a zero-length string automatically.
Otherwise it must be set with a non-zero length string.
The SET operation of this object must be with the SET
operation of hh3cDhcpSnoop2IfVlanRIDMode.