Add permission for VFIO device binding

vfio_handler will bind platform devices to VFIO driver, and then
return a file descriptor containing DTBO. This change adds
permissions needed for that.

Bug: 278008182
Test: adb shell /apex/com.android.virt/bin/vm run-microdroid \
      --devices /sys/bus/platform/devices/16d00000.eh --protected
Change-Id: Ie947adff00d138426d4703cbb8e7a8cd429c2272
diff --git a/private/service_contexts b/private/service_contexts
index 94f913d..a85d21d 100644
--- a/private/service_contexts
+++ b/private/service_contexts
@@ -147,6 +147,7 @@
 android.service.gatekeeper.IGateKeeperService    u:object_r:gatekeeper_service:s0
 android.system.composd                    u:object_r:compos_service:s0
 android.system.virtualizationservice      u:object_r:virtualization_service:s0
+android.system.virtualizationservice_internal.IVfioHandler u:object_r:vfio_handler_service:s0
 ambient_context                           u:object_r:ambient_context_service:s0
 app_binding                               u:object_r:app_binding_service:s0
 app_hibernation                           u:object_r:app_hibernation_service:s0