btrfs: remove root argument from btrfs_log_inode() and its callees

btrfs: remove root argument from btrfs_log_inode() and its callees

The root argument passed to btrfs_log_inode() is unncessary, as it is
always the root of the inode we are going to log. This root also gets
unnecessarily propagated to several functions called by btrfs_log_inode(),
and all of them take the inode as an argument as well. So just remove
the root argument from these functions and have them get the root from
the inode where needed.

This patch is part of a patchset comprised of the following 5 patches:

  btrfs: remove root argument from btrfs_log_inode() and its callees
  btrfs: remove redundant log root assignment from log_dir_items()
  btrfs: factor out the copying loop of dir items from log_dir_items()
  btrfs: insert items in batches when logging a directory when possible
  btrfs: keep track of the last logged keys when logging a directory

This is patch 1/5. The change log of the last patch (5/5) has performance
results.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>