DLSS/FSR settings improvements

[Leroy231]

• [ ] When you enable/disable DLSS/FSR settings we should gray out settings that aren't usable immediately. Also you shouldn't have to apply first to toggle other setting (e.g. if you just disabled DLSS settings you should immediately be able to enable FSR settings without hitting apply first).
• [ ] Try to figure out a way to fix a bug when DLSS doesn't apply sometimes. Repro:
  1. Enable FSR-FI and apply settings.
  2. Restart the game (editor when running game from it).
  3. Try to enable DLSS-FG. Restart game after pressing Yes on the notification pop up.
  4. The DLSS-FG didn't enable. WARNING: Keep in mind that this happens because when we enable FSR and disable both StreamLineD3D11/12 the editor doesn't load StreamLineRHI module and default DLSS implementation of the method "IsNvidiaDLSS-FGSupporteed" won't return correct result.