libblkid: fix topology information values

libblkid: fix topology information values

Looks like the topology values returned are being
inflated by x 512, but the kernel reports them in bytes;
no need for the multiplication, just return the value as-is.

With the patch it all matches:

# mdadm -D /dev/md0  | grep Chunk
     Chunk Size : 64K
# cat /sys/devices/virtual/block/md0/queue/minimum_io_size
65536
# blkid/samples/topology /dev/md0
----- NAME=value interface (values: 0):
	MINIMUM_IO_SIZE = 65536
	OPTIMAL_IO_SIZE = 131072
----- binary interface:
alignment offset : 0
minimum io size  : 65536
optimal io size  : 131072

Signed-off-by: Eric Sandeen <sandeen@redhat.com>