Removed UWP from OpenVR supported platforms

Author: keveleigh

Assets/MixedRealityToolkit-SDK/Profiles/DefaultMixedRealityRegisteredComponentsProfile.asset

@@ -24,7 +24,7 @@ MonoBehaviour:
         Microsoft.MixedReality.Toolkit
     componentName: Unity Open VR Device Manager
     priority: 10
-    runtimePlatform: -1
+    runtimePlatform: 7
     configurationProfile: {fileID: 0}
   - componentType:
       reference: Microsoft.MixedReality.Toolkit.Core.Devices.WindowsMixedReality.WindowsMixedRealityDeviceManager,