Remove compatibility rules for old /data/media type.

These are obsoleted by the restorecon_recursive /data/media call
added to the device init*.rc files, e.g.
see I4a191d32a46104a68f6644398c152b274c7937a6
for the hammerhead change.

If/when Ib8d9751a47c8e0238cf499fcec61898937945d9d is merged, this
will also be addressed for all devices by the restorecon_recursive /data
call added to the main init.rc file.

Change-Id: Idbe2006a66817d6bb284d138a7565dec24dc6745
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>