datapath: Always define NF_CT_LABELS_MAX_SIZE

When CONFIG_NF_CONNTRACK_LABLES is not set, upstream code still make
use of NF_CT_LABLES_MAX_SIZE. Always define it in the compat code
to keep back ports close to the upstream.

Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>

datapath/linux/compat/include/net/netfilter/nf_conntrack_labels.h

@@ -5,13 +5,13 @@
 #include <linux/version.h>
 #include_next <net/netfilter/nf_conntrack_labels.h>
 
-#ifndef HAVE_NF_CONNLABELS_GET_TAKES_BIT
-#if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
-
 #ifndef NF_CT_LABELS_MAX_SIZE
 #define NF_CT_LABELS_MAX_SIZE ((XT_CONNLABEL_MAXBIT + 1) / BITS_PER_BYTE)
 #endif
 
+#ifndef HAVE_NF_CONNLABELS_GET_TAKES_BIT
+#if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
+
 /* XXX: This doesn't lock others out from doing the same configuration
  *	simultaneously. */
 static inline int rpl_nf_connlabels_get(struct net *net, unsigned int bits)