mm/page_alloc: Remove kernel address exposure in free_reserved_area()

commit adb1fe9a upstream.

Linus suggested we try to remove some of the low-hanging fruit related
to kernel address exposure in dmesg.  The only leaks I see on my local
system are:

  Freeing SMP alternatives memory: 32K (ffffffff9e309000 - ffffffff9e311000)
  Freeing initrd memory: 10588K (ffffa0b736b42000 - ffffa0b737599000)
  Freeing unused kernel memory: 3592K (ffffffff9df87000 - ffffffff9e309000)
  Freeing unused kernel memory: 1352K (ffffa0b7288ae000 - ffffa0b728a00000)
  Freeing unused kernel memory: 632K (ffffa0b728d62000 - ffffa0b728e00000)

Linus says:

  "I suspect we should just remove [the addresses in the 'Freeing'
   messages]. I'm sure they are useful in theory, but I suspect they
   were more useful back when the whole "free init memory" was
   originally done.

   These days, if we have a use-after-free, I suspect the init-mem
   situation is the easiest situation by far. Compared to all...

mm/page_alloc.c

@@ -6445,8 +6445,8 @@ unsigned long free_reserved_area(void *start, void *end, int poison, char *s)
 	}
 
 	if (pages && s)
-		pr_info("Freeing %s memory: %ldK (%p - %p)\n",
-			s, pages << (PAGE_SHIFT - 10), start, end);
+		pr_info("Freeing %s memory: %ldK\n",
+			s, pages << (PAGE_SHIFT - 10));
 
 	return pages;
 }