ide-cd: clear sense buffer before issuing request sense

Impact: code simplification

ide_cd_request_sense_fixup() clears the tail of the sense buffer if
the device didn't completely fill it.  This patch makes
cdrom_queue_request_sense() clear the sense buffer before issuing the
command instead of clearing it afterwards.  This simplifies code and
eases future changes.

Signed-off-by: Tejun Heo <tj@kernel.org>