Re-arrange the fields in the VMOD object struct a bit.

Still very cacheline-unfriendly.

src/vmod_file.c

@@ -90,15 +90,15 @@ struct file_info {
 struct VPFX(file_reader) {
 	unsigned		magic;
 #define FILE_READER_MAGIC 0x08d18e5b
+	int			flags;
 	pthread_rwlock_t	lock;
 	struct file_info	*info;
 	char			*addr;
 	char			*vcl_name;
 	char			*obj_name;
 	char			*errbuf;
-	size_t			errlen;
 	timer_t			timerid;
-	int			flags;
+	uint8_t			errlen;
 };
 
 struct timer_entry {