SELinux: Add new labeling type native labels

SELinux: Add new labeling type native labels

There currently doesn't exist a labeling type that is adequate for use with
labeled NFS. Since NFS doesn't really support xattrs we can't use the use xattr
labeling behavior. For this we developed a new labeling type. The native
labeling type is used solely by NFS to ensure NFS inodes are labeled at runtime
by the NFS code instead of relying on the SELinux security server on the client
end.

Acked-by: Eric Paris <[email protected]>
Acked-by: James Morris <[email protected]>
Signed-off-by: Matthew N. Dodd <[email protected]>
Signed-off-by: Miguel Rodel Felipe <[email protected]>
Signed-off-by: Phua Eu Gene <[email protected]>
Signed-off-by: Khin Mi Mi Aung <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>