fuse: use correct name fuse_conn_list in docstring

fuse_mount_list doesn't exist, use fuse_conn_list.

Signed-off-by: Aurelien Aptel <aaptel@nvidia.com>
Reviewed-by: Bernd Schubert <bschubert@ddn.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>