Slightly correct context check for event triggers

The previous check for a "complete query" omitted the new
PROCESS_UTILITY_QUERY_NONATOMIC value.  This didn't actually make a
difference in practice, because only CALL and SET from PL/pgSQL run in
this state, but it's more correct to include it anyway.

Discussion: https://www.postgresql.org/message-id/4566041d-2567-74d2-d135-19ff6a20fe51%402ndquadrant.com

Author: petere

src/backend/tcop/utility.c

@@ -943,7 +943,7 @@ ProcessUtilitySlow(ParseState *pstate,
 {
 	Node	   *parsetree = pstmt->utilityStmt;
 	bool		isTopLevel = (context == PROCESS_UTILITY_TOPLEVEL);
-	bool		isCompleteQuery = (context <= PROCESS_UTILITY_QUERY);
+	bool		isCompleteQuery = (context != PROCESS_UTILITY_SUBCOMMAND);
 	bool		needCleanup;
 	bool		commandCollected = false;
 	ObjectAddress address;