[settings,qt] merge of "disable controller applet" toggle with "controller applet mode" picker (#4498)

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-------------------
Small good simplification to nuke a toggle which costed me almost an entire day of work when fixing controller applet issues:

There were two settings related to Controller applet:
-"disable controller applet", which is a boolean toggle;
-"controller configuration" applet mode, which is a "Real"/"Custom" picker;

All i did was to nuke the toggle and add a third option "Disabled" to the picker.
Users which used the disable toggle will have to pick Disabled;
Real/Custom settings wont be affected since their indexes remains.
All options tested against diablo 3. All working as intended.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4498
Reviewed-by: lizzie <lizzie@eden-emu.dev>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>

src/yuzu/main_window.cpp

@@ -1786,7 +1786,7 @@ bool MainWindow::LoadROM(const QString& filename, Service::AM::FrontendAppletPar
 
     QtCommon::system->SetFrontendAppletSet({
         std::make_unique<QtAmiiboSettings>(*this), // Amiibo Settings
-        (UISettings::values.controller_applet_disabled.GetValue() == true)
+        (Settings::values.controller_applet_mode.GetValue() == Settings::AppletMode::Disabled)
             ? nullptr
             : std::make_unique<QtControllerSelector>(*this), // Controller Selector
         std::make_unique<QtErrorDisplay>(*this),             // Error Display