Fix crosvm gpu device access to host video devices

modules/services.nix

@@ -651,9 +651,8 @@ in
                 ];
                 MountAPIVFS = true;
 
-                #PrivateDevices = true;
                 DeviceAllow = [
-                  "/dev/dri rw"
+                  "char-drm rw"
                   "/dev/udmabuf rw"
                 ];