FFmpeg 7 removed AVCodecParameters.channels, causing MiniDLNA 1.3.3
to fail to compile when reading audio channel counts.
Add an OpenWrt package patch to use ch_layout.nb_channels with
libavcodec 61 and later. Retain the existing channels field access
for older versions.
Signed-off-by: Marcin Maj <marcinmajsc@gmail.com>