Revert this, and do it differently: prefer the preferred song/course in

MusicWheel::SelectSongOrCourse instead of the active one.  The advantage
of this is that if, for example, a PreferredCourse is set, the player is playing
regular play (not course mode), and then switches to course mode via the
mode menu, the course will be selected correctly.  (Previously, it'd end up
on the default course in that case instead.)

stepmania/src/ScreenSelectMusic.cpp

@@ -71,15 +71,6 @@ ScreenSelectMusic::ScreenSelectMusic( CString sClassName ) : ScreenWithMenuEleme
 	/* Finish any previous stage.  It's OK to call this when we havn't played a stage yet. 
 	 * Do this before anything that might look at GAMESTATE->m_iCurrentStageIndex. */
 	GAMESTATE->FinishStage();
-
-	/* If we have a preferred song, let it override the active song.  That way, you
-	 * can set PreferredSong at any time (eg. during initial menus or evaluation) to
-	 * select the default song for the next play, without interfering with things
-	 * that still need pCurSong. */
-	if( GAMESTATE->m_pPreferredSong )
-		GAMESTATE->m_pCurSong.Set( GAMESTATE->m_pPreferredSong );
-	if( GAMESTATE->m_pPreferredCourse )
-		GAMESTATE->m_pCurCourse = GAMESTATE->m_pPreferredCourse;
 }