cmd64x: fix hwif->chipset setup

commit 528a572daea90aa41db92683e5a8756acef514c4 ("ide: add ->chipset field
to ide_pci_device_t") broke hwif->chipset setup (it is now set to ide_cmd646
for CMD648 instead of CMD646).  It seems that the breakage happend while
I was moving patches around (cmd64x_chipsets[] entries for CMD646 and CMD648
are identical except for 'name' field).  Fix it and bump driver version.

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