btrfs: print-tree: print information about inode ref items

btrfs: print-tree: print information about inode ref items

Currently we ignore inode ref items, we just print their key, item offset
in the leaf and their size, no information about their content like the
index number, name length and name.

Improve on this by printing the index and name length in the same format
as btrfs-progs. Note that we don't print the name, as that would require
some processing and escaping like we do in btrfs-progs, and that could
expose sensitive information for some users in case they share their
dmesg/syslog and it contains a leaf dump. So for now leave names out.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>