drbd: allow petabyte storage on 64bit arch

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

diff --cc drivers/block/drbd/drbd_bitmap.c
Simple merge

diff --cc drivers/block/drbd/drbd_int.h
Simple merge

diff --cc drivers/block/drbd/drbd_nl.c
Simple merge

diff --cc drivers/block/drbd/drbd_proc.c
Simple merge

diff --cc drivers/block/drbd/drbd_worker.c
Simple merge