ide-cd: coding style fixes for cdrom_get_toc_entry()

This is a preparation to move code handling cdrom.c IOCTLs out of ide-cd.c.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>