mm/memory.c: fix typo in __do_fault() comment

It's "pte_alloc_one", not "pte_alloc_pne". Let's fix that.
Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: http://lkml.kernel.org/r/20200818104339.5310-1-yanfei.xu@windriver.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory.c

@@ -3589,7 +3589,7 @@ static vm_fault_t __do_fault(struct vm_fault *vmf)
 	 *				unlock_page(A)
 	 * lock_page(B)
 	 *				lock_page(B)
-	 * pte_alloc_pne
+	 * pte_alloc_one
 	 *   shrink_page_list
 	 *     wait_on_page_writeback(A)
 	 *				SetPageWriteback(B)