Allow drmserver to read the wv keys.

Bug: 8539042
Change-Id: I31e7a3ae6ba783b78c3b38756966950a20f2f2aa
diff --git a/drmserver.te b/drmserver.te
index 9ef3189..bfd8251 100644
--- a/drmserver.te
+++ b/drmserver.te
@@ -23,3 +23,4 @@
 allow drmserver platform_app_data_file:file { read write getattr };
 allow drmserver app_data_file:file { read write getattr };
 allow drmserver sdcard_type:file { read write getattr };
+allow drmserver efs_file:file { open read getattr };