Renaming COMPPREDMODE_TYPE enum and its members.

List of renames:
  COMPPREDMODE_TYPE      => REFERENCE_MODE
  SINGLE_PREDICTION_ONLY => SINGLE_REFERENCE
  COMP_PREDICTION_ONLY   => COMPOUND_REFERENCE
  HYBRID_PREDICTION      => REFERENCE_MODE_SELECT (like TX_MODE_SELECT)
  NB_PREDICTION_TYPES    => REFERENCE_MODES

Change-Id: If723dabe9435325d0165dcd028142a2c78b417b4