Fix dialogs title bar broken by Windows CE removal changes

Restore the code setting WS_CAPTION that was mistakenly removed in
8282c1be0f

See https://github.com/wxWidgets/wxWidgets/pull/81

Closes #17161.

src/msw/toplevel.cpp

@@ -141,6 +141,11 @@ WXDWORD wxTopLevelWindowMSW::MSWGetStyle(long style, WXDWORD *exflags) const
     else
         msflags |= WS_POPUP;
 
+    if ( style & wxCAPTION )
+        msflags |= WS_CAPTION;
+    else
+        msflags |= WS_POPUP;
+
     // next translate the individual flags
 
     // WS_EX_CONTEXTHELP is incompatible with WS_MINIMIZEBOX and WS_MAXIMIZEBOX