Documentation typo: wrong page flag bit for KPF_HUGE

The correct value 17 can be found later in this document
and in the kernel-page-flags.h header (KPF_HUGE). I noticed
this while implementing vmprobe's kpageflags support.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/Documentation/vm/pagemap.txt b/Documentation/vm/pagemap.txt
index 0e1e555..eafcefa 100644
--- a/Documentation/vm/pagemap.txt
+++ b/Documentation/vm/pagemap.txt
@@ -62,7 +62,7 @@
     14. SWAPBACKED
     15. COMPOUND_HEAD
     16. COMPOUND_TAIL
-    16. HUGE
+    17. HUGE
     18. UNEVICTABLE
     19. HWPOISON
     20. NOPAGE