- Synchronize with 2.5.8.

- Eliminate the cdrom_log_sense() function.

- Pass a struct request to cdrom_analyze_sense_data() since this is the entity
   this function is working on. This shows nicely that this function is broken.

- Use CDROM_PACKET_SIZE where appropriate.

- Kill the obfuscating cmd_buf and cmd_len local variables from
   cdrom_transfer_packet_command(). This made it obvious that the parameters of
   this function where not adequate - to say the least. Fix this.

- Pass a packed command array directly to cdrom_queue_packed_command().  This
   is reducing the number of places where we have to deal with the c member of
   struct packet_command.

- Never pass NULL as sense to cdrom_lockdoor().

- Eliminate cdrom_do_block_pc().

- Eliminate the c member of struct packet_command. Pass them through struct
   request cmd member.

- Don't enable TCQ unconditionally if there is a TCQ queue depth defined.

- Fix small think in ide_cmd_ioctl() rewrite. (My appologies to everyone who
   has to use hdparm to setup his system...)

- Fix compilation without PCI support.