netfs: Add Jeff Layton as reviewer

Add Jeff Layton as a reviewer in the MAINTAINERS file.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20240122115007.3820330-3-dhowells@redhat.com
Acked-by: Jeff Layton <jlayton@kernel.org>
cc:  <netfs@lists.linux.dev>
cc:  <linux-fsdevel@vger.kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>