lib: add missing define for scrambled-changed event

This is needed for libvlc_event_type_name().
Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

lib/event.c

@@ -280,6 +280,7 @@ static const event_name_t event_list[] = {
     DEF(MediaPlayerSnapshotTaken)
     DEF(MediaPlayerLengthChanged)
     DEF(MediaPlayerVout)
+    DEF(MediaPlayerScrambledChanged)
 
     DEF(MediaListItemAdded)
     DEF(MediaListWillAddItem)