ext4: add verifier check for symlink with append/immutable flags

ext4: add verifier check for symlink with append/immutable flags

BugLink: https://bugs.launchpad.net/bugs/1837257
The Linux VFS does not allow a way to set append/immuttable
attributes to symlinks, this is just not possible. If this is
detected inform the user as the filesystem must be corrupted.

Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
(cherry picked from commit 6390d33bf5d9b24fd4f96e415b6888f59c8494f9)
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>