mm/kmemleak.c: fix a comment

I noticed a typo in a code comment and I fixed it.

Link: https://lkml.kernel.org/r/20221114171426.91745-1-caoyixuan2019@email.szu.edu.cn
Signed-off-by: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/kmemleak.c

@@ -1461,7 +1461,7 @@ static void scan_gray_list(void)
 }
 
 /*
- * Conditionally call resched() in a object iteration loop while making sure
+ * Conditionally call resched() in an object iteration loop while making sure
  * that the given object won't go away without RCU read lock by performing a
  * get_object() if !pinned.
  *