bcache: Stripe size isn't necessarily a power of two

Originally I got this right... except that the divides didn't use
do_div(), which broke 32 bit kernels. When I went to fix that, I forgot
that the raid stripe size usually isn't a power of two... doh

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 4211d82..b3a66f1 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -157,7 +157,7 @@
 	sysfs_hprint(dirty_data,
 		     bcache_dev_sectors_dirty(&dc->disk) << 9);
 
-	sysfs_hprint(stripe_size,	(1 << dc->disk.stripe_size_bits) << 9);
+	sysfs_hprint(stripe_size,	dc->disk.stripe_size << 9);
 	var_printf(partial_stripes_expensive,	"%u");
 
 	var_printf(sequential_merge,	"%i");