Remove block device access from unconfined domains.

Only allow to domains as required and amend the existing
neverallow on block_device:blk_file to replace the
exemption for unconfineddomain with an explicit whitelist.
The neverallow does not check other device types as specific
ones may need to be writable by device-specific domains.

Change-Id: I0f2f1f565e886ae110a719a08aa3a1e7e9f23e8c
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
diff --git a/init.te b/init.te
index efce6e7..c05faba 100644
--- a/init.te
+++ b/init.te
@@ -9,6 +9,7 @@
 
 allow init self:capability { sys_rawio mknod };
 
+allow init dev_type:blk_file rw_file_perms;
 allow init fs_type:filesystem *;
 allow init {fs_type dev_type file_type}:dir_file_class_set relabelto;
 allow init kernel:security load_policy;