mm: numa: fix minor typo in numa_next_scan

s/me/be/ and clarify the comment a bit when we're changing it anyway.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Suggested-by: Simon Jeons <simon.jeons@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/mm_types.h

@@ -414,9 +414,9 @@ struct mm_struct {
 #endif
 #ifdef CONFIG_NUMA_BALANCING
 	/*
-	 * numa_next_scan is the next time when the PTEs will me marked
-	 * pte_numa to gather statistics and migrate pages to new nodes
-	 * if necessary
+	 * numa_next_scan is the next time that the PTEs will be marked
+	 * pte_numa. NUMA hinting faults will gather statistics and migrate
+	 * pages to new nodes if necessary.
 	 */
 	unsigned long numa_next_scan;