btrfs: don't use token set/get accessors in inode.c:fill_inode_item()

The token versions of set/get accessors will be removed, use the normal
helpers.

There's additional overhead of the token helpers that update the cached
address in case it moves to another page/folio. The normal versions
don't need to do that.

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