ide-scsi: remove needless SELECT_DRIVE() call

SELECT_DRIVE() is called by IDE core code in start_request() before device
driver's ->do_request method.  In ide-scsi case ->do_request is implemented
by idescsi_do_request() which is also the only user of idescsi_issue_pc().

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>