docs/vm: transhuge: fix typo in madvise reference

Fix an off-by-one typo in the transparent huge pages admin
documentation.
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/admin-guide/mm/transhuge.rst

@@ -53,7 +53,7 @@ disabled, there is ``khugepaged`` daemon that scans memory and
 collapses sequences of basic pages into huge pages.
 
 The THP behaviour is controlled via :ref:`sysfs <thp_sysfs>`
-interface and using madivse(2) and prctl(2) system calls.
+interface and using madvise(2) and prctl(2) system calls.
 
 Transparent Hugepage Support maximizes the usefulness of free memory
 if compared to the reservation approach of hugetlbfs by allowing all