When in effect, add "test_dummy_encryption" to _ext4_show_options() so
that it is shown in /proc/mounts and other relevant procfs files.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org