outputchangeset: set default values for vrr policy and rgb range

If this is not done then KScreen will sometimes unintentionally reset them
to the default.

BUG: 442520
FIXED-IN: 5.24.4

src/wayland/outputchangeset_v2.cpp

@@ -21,6 +21,8 @@ OutputChangeSetV2Private::OutputChangeSetV2Private(OutputDeviceV2Interface *outp
     , position(outputDevice->globalPosition())
     , scale(outputDevice->scale())
     , overscan(outputDevice->overscan())
+    , vrrPolicy(outputDevice->vrrPolicy())
+    , rgbRange(outputDevice->rgbRange())
 {
 }