Remove libsigchain from LD_PRELOADs

Bug: 15345057
Bug: 15426766
Change-Id: If0b7f59a59824e30aa0c33dad76c7a44932180de
diff --git a/rootdir/init.environ.rc.in b/rootdir/init.environ.rc.in
index 1f964e3..927c33d 100644
--- a/rootdir/init.environ.rc.in
+++ b/rootdir/init.environ.rc.in
@@ -9,4 +9,3 @@
     export ASEC_MOUNTPOINT /mnt/asec
     export LOOP_MOUNTPOINT /mnt/obb
     export BOOTCLASSPATH %BOOTCLASSPATH%
-    export LD_PRELOAD libsigchain.so