BACKPORT: smack: allow mount opts setting over filesystems with binary mount data

BACKPORT: smack: allow mount opts setting over filesystems with binary mount data

Add support for setting smack mount labels(using smackfsdef, smackfsroot,
smackfshat, smackfsfloor, smackfstransmute) for filesystems with binary
mount data like NFS.

To achieve this, implement sb_parse_opts_str and sb_set_mnt_opts security
operations in smack LSM similar to SELinux.

Signed-off-by: Vivek Trivedi <t.vivek@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
(cherry-picked from upstream 3bf2789cad9e6573dc19a6c3d123c2c049f2d90f)