Add HDR support with software decoding using libplacebo

Not supported on macOS yet.

app/gui/SettingsView.qml

@@ -1498,7 +1498,6 @@ Flickable {
 
                     id: decoderComboBox
                     textRole: "text"
-                    enabled: !enableHdr.checked
                     model: ListModel {
                         id: decoderListModel
                         ListElement {
@@ -1520,21 +1519,6 @@ Flickable {
                             StreamingPreferences.videoDecoderSelection = decoderListModel.get(currentIndex).val
                         }
                     }
-
-                    // This handles the state of the enableHdr checkbox changing
-                    onEnabledChanged: {
-                        if (enabled) {
-                            StreamingPreferences.videoDecoderSelection = decoderListModel.get(currentIndex).val
-                        }
-                        else {
-                            StreamingPreferences.videoDecoderSelection = StreamingPreferences.VDS_AUTO
-                        }
-                    }
-
-                    ToolTip.delay: 1000
-                    ToolTip.timeout: 5000
-                    ToolTip.visible: hovered && !enabled
-                    ToolTip.text: qsTr("Enabling HDR overrides manual decoder selections.")
                 }
 
                 Label {