kernel: exit: fix typo in comment

s,critiera,criteria,

While at it, add a comma, because it makes sense grammatically.
Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

kernel/exit.c

@@ -1471,7 +1471,7 @@ static long do_wait(struct wait_opts *wo)
 	add_wait_queue(&current->signal->wait_chldexit, &wo->child_wait);
 repeat:
 	/*
-	 * If there is nothing that can match our critiera just get out.
+	 * If there is nothing that can match our criteria, just get out.
 	 * We will clear ->notask_error to zero if we see any child that
 	 * might later match our criteria, even if we are not able to reap
 	 * it yet.