Fix various typos and spelling mistakes

Source/Core/DolphinQt/Debugger/CodeViewWidget.cpp

@@ -676,7 +676,7 @@ void CodeViewWidget::OnContextMenu()
 
   auto* note = m_ppc_symbol_db.GetNoteFromAddr(addr);
   note_edit_action->setEnabled(note != nullptr);
-  // A note cannot be added ontop of the starting address of another note.
+  // A note cannot be added on top of the starting address of another note.
   if (note != nullptr && note->address == addr)
     note_add_action->setEnabled(false);
 

Source/Core/DolphinQt/Debugger/MemoryViewWidget.cpp

@@ -984,7 +984,7 @@ void MemoryViewWidget::ToggleHighlights(bool enabled)
   }
   else
   {
-    // Treated as being interchangable with Qt::transparent.
+    // Treated as being interchangeable with Qt::transparent.
     m_highlight_color.setAlpha(0);
 
     // Immediately remove highlights when paused.
@@ -1220,7 +1220,7 @@ void MemoryViewWidget::OnContextMenu(const QPoint& pos)
 
   auto* note = m_ppc_symbol_db.GetNoteFromAddr(addr);
   note_edit_action->setEnabled(note != nullptr);
-  // A note cannot be added ontop of the starting address of another note.
+  // A note cannot be added on top of the starting address of another note.
   if (note != nullptr && note->address == addr)
     note_add_action->setEnabled(false);
 

Source/Core/DolphinQt/Debugger/RegisterColumn.h

@@ -31,7 +31,7 @@ enum class RegisterType
   int_mask,    // ???
   int_cause,   // ???
   dsisr,       // Defines the cause of data / alignment exceptions
-  dar,         // Data adress register
+  dar,         // Data address register
   pt_hashmask  // ???
 };