mm/page_alloc.c: clean up comment

Signed-off-by: NYaowei Bai <bywxiaobai@163.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -5760,7 +5760,7 @@ static void __setup_per_zone_wmarks(void)
 			 * value here.
 			 *
 			 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
-			 * deltas controls asynch page reclaim, and so should
+			 * deltas control asynch page reclaim, and so should
 			 * not be capped for highmem.
 			 */
 			unsigned long min_pages;