Use command->sc_data_direction instead of trying (incorrectly) to
figure it out from the command itself

[jejb: fix up compile failure]
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Acked-by: NNickCheng <nick.cheng@areca.com.tw>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>