move /data/tombstone creation to system/core

Bug: https://code.google.com/p/android/issues/detail?id=93207
Change-Id: Ib65bc78e680cc79b44f8ab29b331db3af9a29d0e
diff --git a/init.shamu.rc b/init.shamu.rc
index e5b5afb..e134727 100644
--- a/init.shamu.rc
+++ b/init.shamu.rc
@@ -76,7 +76,6 @@
     setprop persist.data.df.agg.dl_size 4096
 
 on post-fs-data
-    mkdir /data/tombstones 0771 system system
     mkdir /tombstones/modem 0771 system system
     mkdir /tombstones/lpass 0771 system system
     mkdir /tombstones/wcnss 0771 system system