[PATCH] 2.5.8 IDE 37

[PATCH] 2.5.8 IDE 37

- Don't abuse the sense field for passing failed packet_commands in struct
   packet_command use a new field instead.

- Apply minor bits forwarded by Dave Jones to me.

- Fix ide_raw_taskfile() to flag the ar used there to be no subject of free_req
   list management. This solvs the "hang after /proc/ide read" problem, which
   was in fact a memory corruption problem.