pata_arasan_cf: Delete an unnecessary variable initialisation in arasan_cf_probe()

The local variable "ret" will eventually be set to an appropriate value
a bit later. Thus omit the explicit initialisation at the beginning.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Tejun Heo <tj@kernel.org>