rtpproto: Add an option for writing return packets to the address of the last received packets

If we've received packets on the same socket before, the return
packets are sent to that address. If we've only received packets
on the other socket, try to guess the source port for the other
one assuming the basic +1/-1 logic.

Signed-off-by: Martin Storsjö <martin@martin.st>
sdp: Add an option for sending RTCP packets to the source of the last packets

An SDP description normally only contains the target IP address
and port for the packets. This means that we don't really have
any clue where to send the RTCP RR packets - previously they're
sent to the destination IP written in the SDP (at the same port),
which rarely is the actual peer. And if the source for the packets
is on a different port than the destination, it's never correct.

With a new option, we can choose to send the packets to the
address that the latest packet on each socket arrived from.
---
Some may even argue that this should be the default - perhaps,
but I'd rather keep it optional at first. Additionally, I'm not
sure if sending RTCP RR directly back to the source is
desireable for e.g. multicast.

Signed-off-by: Martin Storsjö <martin@martin.st>
rtpproto: Check for the right feature when reading a sockaddr_in6

Some systems, such as OS/2, define AF_INET6 without a full
implementation.

Signed-off-by: Martin Storsjö <martin@martin.st>
8bps: decode 24bit files correctly as rgb32 on bigendian
electronicarts: K&R formatting cosmetics
electronicarts: Remove bogus function documentation
electronicarts: comment wording fixes
electronicarts: Improve some function/variable names
electronicarts: Let functions always returning the same value return void
rtpproto: Check the right feature detection macro

IPPROTO_IPV6 is unrelated here (it's only used in udp.c for
multicast sockopts), check for support for the sockaddr_in6
struct itself.

Signed-off-by: Martin Storsjö <martin@martin.st>
ivi_common: Make some tables only used within the file static
swscale: Mark a bunch of tables only used within one file static
swscale: Move extern declarations for tables to swscale_internal.h

Also add missing ff_ prefixes where necessary.
avcodec: Replace local extern declarations for tables with header #includes
mpeg12decdata: Remove unused #define
mpeg12decdata.h: Move all tables to the only place they are used
vp56data: Move all shared enum/struct declarations to common header
vp56data: Move all data tables to the .c file
hlsenc: Add a proper dependency on the mpegts muxer

The hls muxer itself doesn't have any direct (object file level)
dependencies on mpegtsenc.o, and including that object file
directly doesn't ensure that it is registered so that the muxer
actually is accessible.

Signed-off-by: Martin Storsjö <martin@martin.st>
hlsenc: Append the last incomplete segment when closing the output

Also avoid comparing NOPTS values.

Bug-id: 551
Signed-off-by: Martin Storsjö <martin@martin.st>