Fix invalidated iterator when removing notes in Piano Roll (#7080)

* Fix invalidated iterator when removing notes in Piano Roll

* fixup - typo

* Add MidiClip::removeNote(iterator) function

* Use iterator version of remoteNote

* Fix parameter name

* Change variable name again

include/MidiClip.h

@@ -63,7 +63,8 @@ public:
 	// note management
 	Note * addNote( const Note & _new_note, const bool _quant_pos = true );
 
-	void removeNote( Note * _note_to_del );
+	NoteVector::const_iterator removeNote(NoteVector::const_iterator it);
+	NoteVector::const_iterator removeNote(Note* note);
 
 	Note * noteAtStep( int _step );