openflow_input: rename OF 1.4 match to match_v3

This matches OF 1.3. We should probably rename this struct to match_oxm.
diff --git a/openflow_input/standard-1.4 b/openflow_input/standard-1.4
index d7e38eb..5766411 100644
--- a/openflow_input/standard-1.4
+++ b/openflow_input/standard-1.4
@@ -834,8 +834,7 @@
     list(of_port_mod_prop_t) properties;
 };
 
-// FIXME Does this need to be v4?
-struct of_match_v4(align=8, length_includes_align=False) {
+struct of_match_v3(align=8, length_includes_align=False) {
     uint16_t type == 1;
     uint16_t length;
     list(of_oxm_t) oxm_list;