|Describes the operation that resulted in generation
of cpimRPMappingChange notification.
o newMapping, as the name suggests indicates that a new
mapping has been added into the pimRPSetTable,
o deletedMapping indicates that a mapping has been
deleted from the pimRPSetTable, and,
o modifiedXXXMapping indicates that an RP mapping (which
already existed in the table) has been modified.
The two modifications types i.e. modifiedOldMapping
and modifiedNewMapping, are defined to differentiate
the notification generated before modification from
that generated after modification.