When calling OggSeekFindEOS() from inside a OggVisitor callback, then
the #InputStream may be in the middle of an Ogg packet, and the newly
initialized #ogg_sync_state will not be able to load it without the
help of ogg_sync_pageseek(). By passing "synced=false" to
OggSeekFindEOS(), we force the use of ogg_sync_pageseek() even when
not actually seeking.
Closes https://github.com/MusicPlayerDaemon/MPD/issues/719
Since we switched from autotools to Meson in commit
94592c1406, we don't need to include
`config.h` early to properly enable large file support. Meson passes
the required macros on the compiler command line instead of defining
them in `config.h`.
This means we can include `config.h` at any time, whenever we want to
check its macros, and there are no ordering constraints.