ext/phar: mark phar_dostat() as static and mark parameters as const (#21908)

And remove unused declaration from dirstream.c file

Author: Girgias

ext/phar/dirstream.c

@@ -19,8 +19,6 @@
 #include "phar_internal.h"
 #include "dirstream.h"
 
-void phar_dostat(phar_archive_data *phar, phar_entry_info *data, php_stream_statbuf *ssb, bool is_dir);
-
 static const php_stream_ops phar_dir_ops = {
 	phar_dir_write, /* write */
 	phar_dir_read,  /* read  */

ext/phar/stream.c

@@ -482,7 +482,7 @@ static int phar_stream_flush(php_stream *stream) /* {{{ */
 /**
  * stat an opened phar file handle stream, used by phar_stat()
  */
-void phar_dostat(phar_archive_data *phar, phar_entry_info *data, php_stream_statbuf *ssb, bool is_temp_dir)
+static void phar_dostat(const phar_archive_data *phar, const phar_entry_info *data, php_stream_statbuf *ssb, bool is_temp_dir)
 {
 	memset(ssb, 0, sizeof(php_stream_statbuf));