ide-cd: move setting REQ_FAILED flag out from 'end_request' exit path

Move setting REQ_FAILED flag out from 'end_request' exit path in
cdrom_newpc_intr() and also rename 'end_request' to 'out_end'.

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>