Allow vold to call to healthd

vold needs to be able to check remaining battery to safely abort
certain operations

Bug: 11985952
Change-Id: I7dfe83f7d1029593882e0e5ad33f90fb29e5532b

vold.te

@@ -80,3 +80,7 @@ allow vold asec_public_file:file { relabelto setattr };
 # Handle wake locks (used for device encryption)
 allow vold sysfs_wake_lock:file rw_file_perms;
 allow vold self:capability2 block_suspend;
+
+# talk to batteryservice
+binder_use(vold)
+binder_call(vold, healthd)