pata_scc: fix compile warning

Missed one during mass conversion (dc14c0c5).  Fix it.  Spotted by
Stephen Rothwell.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>