Cleanup dvbpsi_*_Gather*Sections() function to not call dvbpsi_DeleteSections() twice.
The function dvbpsi_decoder_reset() already does that, so there is no need to do it
inside the gather functions when dvbpsi_ReInit*() is called.
(cherry picked from commit c1d884e6)
Signed-off-by: Jean-Paul Saman <jpsaman@videolan.org>