The function dvbpsi_decoder_psi_section_add() never set p_decoder::i_last_section_number when
adding a new section at the end of the list. This was left to the decoder implementations. However
the correct action would have been to set p_decoder::i_last_section_number in dvbpsi_decoder_psi_section_add().

(cherry picked from commit 7e9f4ed3)