Create /data/per_boot

Bug: 140882488
Test: Booted twice, checked logs to ensure encryption
    is different each time, adb created files in directory.
Cherry-Picked-From: 570d20d2ac875198416dff280b7a4b7adaacac81
Merged-In: I44f746acd1040f7baa9123d4824ba39b194f287b
Change-Id: I44f746acd1040f7baa9123d4824ba39b194f287b
diff --git a/rootdir/init.rc b/rootdir/init.rc
index b475728..0fa9feb 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -797,6 +797,9 @@
 on property:sys.boot_completed=1
     bootchart stop
+    # Setup per_boot directory so other .rc could start to use it on boot_completed
+    exec - system system -- /bin/rm -rf /data/per_boot
+    mkdir /data/per_boot 0700 system system
 # system server cannot write to /proc/sys files,
 # and chown/chmod does not work for /proc/sys/ entries.