Removes a branch from a transaction and returns the outcome of
    the transaction.

    Format

      SYS$END_BRANCH  [efn] ,[flags] ,iosb ,[astadr] ,[astprm] ,tid

                      ,bid

    C Prototype

      int sys$end_branch  (unsigned int efn, unsigned int

                          flags, struct _iosb *iosb, void

                          (*astadr)(__unknown_params), int astprm,

                          unsigned int tid [4], unsigned int bid

                          [4]);