cm: sepolicy: allow kernel to read storage

This fixes issues where the kernel would need to read and write
files from internal or external storage. More specifically, the
kernel needs these rules for USB mass storage to work correctly.

Change-Id: I8cb0307727bc0c464d5470e55275ad808e748ee0
diff --git a/sepolicy/su.te b/sepolicy/su.te
index 9cd6345..473386b 100644
--- a/sepolicy/su.te
+++ b/sepolicy/su.te
@@ -64,4 +64,6 @@
   allow system_app superuser_device:sock_file { read write create setattr unlink getattr };
   allow system_app sudaemon:unix_stream_socket { connectto read write setopt ioctl };
   allow system_app superuser_device:dir { create rw_dir_perms setattr unlink };
+
+  allow kernel sudaemon:fd { use };
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