decoder/OggSyncState: allow skipping up to 64 kB after seek

This is more of what we did in commit 70bd35abe2 because it turns
out there are Ogg-Opus files with pages larger than 40 kB.

Closes https://github.com/MusicPlayerDaemon/MPD/issues/1487

src/lib/xiph/OggSyncState.cxx

@@ -67,7 +67,7 @@ OggSyncState::ExpectPageIn(ogg_stream_state &os)
 bool
 OggSyncState::ExpectPageSeek(ogg_page &page)
 {
-	size_t remaining_skipped = 32768;
+	size_t remaining_skipped = 65536;
 
 	while (true) {
 		int r = ogg_sync_pageseek(&oy, &page);