raid5-cache: clean up r5l_get_meta

Remove the only partially used local 'io' variable to simplify the code
flow.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>

drivers/md/raid5-cache.c

@@ -322,16 +322,12 @@ static struct r5l_io_unit *r5l_new_meta(struct r5l_log *log)
 
 static int r5l_get_meta(struct r5l_log *log, unsigned int payload_size)
 {
-	struct r5l_io_unit *io;
-
-	io = log->current_io;
-	if (io && io->meta_offset + payload_size > PAGE_SIZE)
+	if (log->current_io &&
+	    log->current_io->meta_offset + payload_size > PAGE_SIZE)
 		r5l_submit_current_io(log);
-	io = log->current_io;
-	if (io)
-		return 0;
 
-	log->current_io = r5l_new_meta(log);
+	if (!log->current_io)
+		log->current_io = r5l_new_meta(log);
 	return 0;
 }