Use fallthrough statement attribute (moar)

lib/kafs/rxkad_kdf.c

@@ -209,8 +209,8 @@ _kafs_derive_des_key(krb5_enctype enctype, void *keydata, size_t keylen,
 	ret = compress_parity_bits(keydata, &keylen);
 	if (ret)
 	    return ret;
-        fallthrough
 	/* FALLTHROUGH */
+        fallthrough
     default:
 	if (enctype < 0)
 	    return KRB5_PROG_ETYPE_NOSUPP;