btrfs: output more info when duplicated ordered extent is found

btrfs: output more info when duplicated ordered extent is found

During development of a new feature, I triggered that btrfs_panic()
inside insert_ordered_extent() and spent quite some unnecessary before
noticing I'm passing incorrect flags when creating a new ordered extent.

Unfortunately the existing error message is not providing much help.

Enhance the output to provide file offset, num bytes and flags of both
existing and new ordered extents.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>