Spelling fixed for comments and a wxASSERT_MSG. Fixes #14022.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70625 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/odcombo.cpp

@@ -375,7 +375,7 @@ bool wxVListBoxComboPopup::HandleKey( int keycode, bool saturate, wxChar keychar
 
     // The m_combo->SetValue() call above sets m_value to the index of this
     // string. But if there are more identical string, the index is of the
-    // first occurence, which may be wrong, so set the index explicitly here,
+    // first occurrence, which may be wrong, so set the index explicitly here,
     // _after_ the SetValue() call.
     m_value = value;