ide: Get rid of CMD646BAR struct

ide: Get rid of CMD646BAR struct

Now that no CMD646 specific parts are left in CMD646BAR (all remaining
members are really PCI IDE specific) this struct can be deleted moving
the memory regions for PCI IDE BARs to PCIIDEState where they better
belong. The CMD646 PCI IDE model is adjusted accordingly.

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 4b6cb2ae150dc0d21178209e4beb1e35140a7325.1547166960.git.balaton@eik.bme.hu
Signed-off-by: John Snow <jsnow@redhat.com>