MINOR: stick-tables: Add GPC0 actions

This patch adds access to GPC0 through http and tcp actions
diff --git a/include/types/action.h b/include/types/action.h
index 5d1b250..4d438c1 100644
--- a/include/types/action.h
+++ b/include/types/action.h
@@ -132,6 +132,9 @@
 		} vars;
 		struct {
 			int sc;
+		} gpc;
+		struct {
+			int sc;
 			long long int value;
 		} gpt;
 		struct track_ctr_prm trk_ctr;