Properly initialize _override executor globals

These have been introduced a while ago[1], but their initialization has
been overlooked.  Since we cannot rely on TLS variables to be zeroed,
we catch up on this.

[1] <php@e3ef7bb>

Co-authored-by: Ilija Tovilo <ilija.tovilo@me.com>

Closes phpGH-16658.

Author: cmb69

Zend/zend.c

@@ -803,6 +803,8 @@ static void executor_globals_ctor(zend_executor_globals *executor_globals) /* {{
 	executor_globals->record_errors = false;
 	executor_globals->num_errors = 0;
 	executor_globals->errors = NULL;
+	executor_globals->filename_override = NULL;
+	executor_globals->lineno_override = -1;
 #ifdef ZEND_MAX_EXECUTION_TIMERS
 	executor_globals->pid = 0;
 	executor_globals->oldact = (struct sigaction){0};