Add uhid permission to virtual_touchpad

Bug: 133012518
Test: Build system and check vr-virtual-touchpad created
Change-Id: Ie1d5bf99554bbd561dfce872ddc789191d61a91c
diff --git a/services/vr/virtual_touchpad/virtual_touchpad.rc b/services/vr/virtual_touchpad/virtual_touchpad.rc
index 99315ef..0de0f9e 100644
--- a/services/vr/virtual_touchpad/virtual_touchpad.rc
+++ b/services/vr/virtual_touchpad/virtual_touchpad.rc
@@ -1,5 +1,5 @@
 service virtual_touchpad /system/bin/virtual_touchpad
   class core
   user system
-  group system input
+  group system input uhid
   writepid /dev/cpuset/system/tasks