selinux: Add SCTP support

The SELinux SCTP implementation is explained in:
Documentation/security/SELinux-sctp.rst

Signed-off-by: Richard Haines <richard_c_haines@btinternet.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h
index 3d54468..dabf028 100644
--- a/security/selinux/include/objsec.h
+++ b/security/selinux/include/objsec.h
@@ -130,6 +130,10 @@
 	u32 sid;			/* SID of this object */
 	u32 peer_sid;			/* SID of peer */
 	u16 sclass;			/* sock security class */
+	enum {				/* SCTP association state */
+		SCTP_ASSOC_UNSET = 0,
+		SCTP_ASSOC_SET,
+	} sctp_assoc_state;
 };
 
 struct tun_security_struct {