Fixed bug #72028 (pg_query_params(): NULL converts to empty string)

I don't have a pgsql server by hand, so no test script, but the fix must
be right.

Author: laruence

NEWS

@@ -11,6 +11,8 @@ PHP                                                                        NEWS
     leads to fatal error). (Laruence)
 
 - Postgres:
+  . Fixed bug #72028 (pg_query_params(): NULL converts to empty string).
+    (Laruence)
   . Fixed bug #71062 (pg_convert() doesn't accept ISO 8601 for datatype
     timestamp). (denver at timothy dot io)
 

ext/pgsql/pgsql.c

@@ -1968,7 +1968,7 @@ PHP_FUNCTION(pg_query_params)
 		params = (char **)safe_emalloc(sizeof(char *), num_params, 0);
 
 		ZEND_HASH_FOREACH_VAL(Z_ARRVAL_P(pv_param_arr), tmp) {
-
+			ZVAL_DEREF(tmp);
 			if (Z_TYPE_P(tmp) == IS_NULL) {
 				params[i] = NULL;
 			} else {