rtpsession: Only put RRs and full SDES into regular RTCP packets
rtpsession: Only put RRs and full SDES into regular RTCP packets

If we may suppress the packet due to the rules of RFC4585 (i.e. when
below the t-rr-int), we can send a smaller RTCP packet without RRs
and full SDES. In theory we could even send a minimal RTCP packet
according to RFC5506, but we don't support that yet.

https://bugzilla.gnome.org/show_bug.cgi?id=746543

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