btrfs-progs: Print more info about device sizes

btrfs-progs: Print more info about device sizes

The entire device size may not be available to the filesystem, eg. if
it's modified via resize. Print this information if it can be obtained
from the DEV_INFO ioctl.

Print the device ID on the same line as the device name and move size to
the next line.

Sample:
/dev/sda7, ID: 3
   Device size:            10.00GiB
   FS occupied:             5.00GiB
   Data,RAID10:           512.00MiB
   Metadata,RAID10:       512.00MiB
   System,RAID10:           4.00MiB
   Unallocated:             9.00GiB

Signed-off-by: David Sterba <dsterba@suse.cz>