fs: fix adding security options to statmount.mnt_opt

fs: fix adding security options to statmount.mnt_opt

Prepending security options was made conditional on sb->s_op->show_options,
but security options are independent of sb options.

Fixes: 056d33137bf9 ("fs: prepend statmount.mnt_opts string with security_sb_mnt_opts()")
Fixes: f9af549d1fd3 ("fs: export mount options via statmount()")
Cc: stable@vger.kernel.org # v6.11
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Link: https://lore.kernel.org/r/20250129151253.33241-1-mszeredi@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>