Allow dumpstate to read /data/tombstones.

Change-Id: Iad32cfb4d5b69176fc551b8339d84956415a4fe7
diff --git a/dumpstate.te b/dumpstate.te
index 279fd98..b2870bc 100644
--- a/dumpstate.te
+++ b/dumpstate.te
@@ -96,3 +96,7 @@
 # Read network state info files.
 allow dumpstate net_data_file:dir search;
 allow dumpstate net_data_file:file r_file_perms;
+
+# Access /data/tombstones.
+allow dumpstate tombstone_data_file:dir r_dir_perms;
+allow dumpstate tombstone_data_file:file r_file_perms;