kernel: relay: remove unnecessary NULL values from relay_open_buf

buf is assigned first, so it does not need to initialize the assignment.

Link: https://lkml.kernel.org/r/20230713234459.2908-1-kunyu@nfschina.comSigned-off-by: Li kunyu <kunyu@nfschina.com>
Reviewed-by: Andrew Morton <akpm@linux-foudation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kernel/relay.c

@@ -375,7 +375,7 @@ static struct dentry *relay_create_buf_file(struct rchan *chan,
  */
 static struct rchan_buf *relay_open_buf(struct rchan *chan, unsigned int cpu)
 {
- 	struct rchan_buf *buf = NULL;
+	struct rchan_buf *buf;
 	struct dentry *dentry;
 
  	if (chan->is_global)