md: Make mddev->array_size sector-based.

This patch renames the array_size field of struct mddev_s to array_sectors
and converts all instances to use units of 512 byte sectors instead of 1k
blocks.

Signed-off-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/faulty.c b/drivers/md/faulty.c
index d107ddc..268547d 100644
--- a/drivers/md/faulty.c
+++ b/drivers/md/faulty.c
@@ -297,7 +297,7 @@
 	rdev_for_each(rdev, tmp, mddev)
 		conf->rdev = rdev;
 
-	mddev->array_size = mddev->size;
+	mddev->array_sectors = mddev->size * 2;
 	mddev->private = conf;
 
 	reconfig(mddev, mddev->layout, -1);