* use 0x00 instead of 0x80 to disable ->{ultra,mwdma,swdma}_mask
* add udma_mask field to ide_pci_device_t and use it to initialize
  ->ultra_mask in aec62xx, cmd64x, pdc202xx_{new,old} and piix drivers
* fix UDMA masks to match with chipset specific *_ratemask()
  (alim15x3, hpt366, serverworks and siimage drivers need UDMA mask
   filtering method - done in the next patch)

v2:
* piix: fix cable detection for 82801AA_1 and 82372FB_1
  [ Noticed by Sergei Shtylyov <sshtylyov@ru.mvista.com>. ]
* cmd64x: use hwif->cds->udma_mask
  [ Suggested by Sergei Shtylyov <sshtylyov@ru.mvista.com>. ]
* aec62xx: fix newly introduced bug - check DMA status not command register
  [ Noticed by Sergei Shtylyov <sshtylyov@ru.mvista.com>. ]

v3:
* piix: use hwif->cds->udma_mask
  [ Suggested by Sergei Shtylyov <sshtylyov@ru.mvista.com>. ]

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>