[NETFILTER]: x_tables: change xt_table_register() return value convention

Switch from 0/-E to ptr/PTR_ERR convention.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
index 90dc6ea..937cebb 100644
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -335,9 +335,9 @@
 			   unsigned int size, const char *table, unsigned int hook,
 			   unsigned short proto, int inv_proto);
 
-extern int xt_register_table(struct xt_table *table,
-			     struct xt_table_info *bootstrap,
-			     struct xt_table_info *newinfo);
+extern struct xt_table *xt_register_table(struct xt_table *table,
+					  struct xt_table_info *bootstrap,
+					  struct xt_table_info *newinfo);
 extern void *xt_unregister_table(struct xt_table *table);
 
 extern struct xt_table_info *xt_replace_table(struct xt_table *table,