The variable window_start in setup_cluster_no_bitmap is not used since commit 1bb91902dc90e25449893e693ad45605cb08fbe5
(Btrfs: revamp clustered allocation logic)
Signed-off-by: Valentina Giusti <valentina.giusti@microon.de> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <clm@fb.com>