Removed ifdefs which should be unneeded with proper XRGraphicsConfig

usage

com.unity.render-pipelines.high-definition/HDRP/Camera/HDCamera.cs

             m_ActualHeight = camera.pixelHeight;
             var screenWidth = m_ActualWidth;
             var screenHeight = m_ActualHeight;
-#if !UNITY_SWITCH
             if (m_frameSettings.enableStereo)
             {
                 screenWidth = XRGraphicsConfig.eyeTextureWidth;
 
                 ConfigureStereoMatrices();
             }
-#endif
 
             // Unfortunately sometime (like in the HDCameraEditor) HDUtils.hdrpSettings can be null because of scripts that change the current pipeline...
             m_msaaSamples = HDUtils.hdrpSettings != null ? HDUtils.hdrpSettings.msaaSampleCount : MSAASamples.None;

com.unity.render-pipelines.high-definition/HDRP/RenderPipeline/HDRenderPipeline.cs

                 return false;
             }
 
-#if !UNITY_SWITCH
             // VR is not supported currently in HD
             if (XRGraphicsConfig.enabled)
             {
             }
-#endif
-
             return true;
         }
 

com.unity.render-pipelines.high-definition/HDRP/RenderPipeline/Settings/FrameSettings.cs

             // Planar and real time cubemap doesn't need post process and render in FP16
             aggregate.enablePostprocess = camera.cameraType != CameraType.Reflection && srcFrameSettings.enablePostprocess;
 
-#if UNITY_SWITCH
-            aggregate.enableStereo = false;
-#else
-#endif
 
             aggregate.enableAsyncCompute = srcFrameSettings.enableAsyncCompute && SystemInfo.supportsAsyncCompute;