rootdir: goldfish: mount debugfs on boot time

goldfish is ported to linux-3.4 and have capability to run atrace.
But can't run atrace yet because debugfs is not mounted on boot time.

Change-Id: I0ce23bde3b8d1b2a88d4238272123e3ab8cb6970
Signed-off-by: Young-Ho Cha <ganadist@gmail.com>
diff --git a/rootdir/etc/init.goldfish.rc b/rootdir/etc/init.goldfish.rc
index a0c1c4f..1373be8 100644
--- a/rootdir/etc/init.goldfish.rc
+++ b/rootdir/etc/init.goldfish.rc
@@ -3,6 +3,7 @@
     mkdir /mnt/sdcard 0000 system system
     # for backwards compatibility
     symlink /mnt/sdcard /sdcard
+    mount debugfs debugfs /sys/kernel/debug
 
 on boot
     setsebool in_qemu 1