Enlarge DUMPED_HEAP_SIZE for 64-bit Windows builds

* src/w32heap.c (DUMPED_HEAP_SIZE): Bump to 23MB.  Reported by
Andy Moreton <andrewjmoreton@gmail.com>.

src/w32heap.c

@@ -116,7 +116,7 @@ typedef struct _RTL_HEAP_PARAMETERS {
    to build only the first bootstrap-emacs.exe with the large size,
    and reset that to a lower value afterwards.  */
 #if defined _WIN64 || defined WIDE_EMACS_INT
-# define DUMPED_HEAP_SIZE (22*1024*1024)
+# define DUMPED_HEAP_SIZE (23*1024*1024)
 #else
 # define DUMPED_HEAP_SIZE (13*1024*1024)
 #endif