Make sure these definitions do not interact with each other.

When p->i_number == p_section->i_number AND p_prev == NULL, then the function
will crash with a segmentation fault. In this case the first element in the linked
list is going to be replaced. The pointer p_prev does not point to a valid sections,
since p is the first element in the list. To solve this case it needs to be treated
seperate.

Signed-off-by: Jean-Paul Saman <jpsaman@videolan.org>

Added dr_4f.{c,h} to src/descriptors/dr.h and src/Makefile.am.
Signed-off-by: Jean-Paul Saman <jpsaman@videolan.org>

Signed-off-by: Jean-Paul Saman <jpsaman@videolan.org>

Various fixes:
- add boundary check for p_decoded->i_references
- fix comments

Signed-off-by: Jean-Paul Saman <jpsaman@videolan.org>

Duplicating p_descriptor->p_decoded which has just been newly create is
wrong. The pointer is empty. What should have been done is duplicating
the pointer p_decoded which is passed to the generator function for the
descriptor.

Decode AAC Audio descriptor 0x7c and identify profile, level and type.

The test on line 348 was wrong. It should test for p->p_next to exist instead
of testing for it being NULL.

Inserting a new PSI section did not take into account that the previous
pointer could be none existing. It was equal to the start of the list,
which resulted in a loop.

(Fixes commit: 57c6cd63)

The member p_decoder->ap_sections[256] is replaced by p_decoder->p_sections.
This is a pointer to a linked list, which makes the dvbpsi_decoder_section_chain()
function obsolete.

Signed-off-by: Jean-Paul Saman <jpsaman@videolan.org>