btrfs: pass walk_control structure to replay_one_dir_item() and replay_one_name()

Instead of passing the transaction and subvolume root and log tree as
arguments, pass the walk_control structure as we can grab all of those
from the structure. This reduces the number of arguments passed and it's
going to be needed by an incoming change that improves error reporting
for log replay.

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