mm/page_table_check: fix typos

Link: https://lkml.kernel.org/r/20220916090434.701194-1-shiyn.lin@gmail.com


Signed-off-by: Chih-En Lin <shiyn.lin@gmail.com>
Acked-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>