ide_pci_setup_ports() from setup-pci.c checks if port is disabled, if so
d->init_setup_dma() and d->init_hwif() won't be called.  There is no
need to check it once again inside init_hwif_via82cxxx(),
init_dma_via82cxxx() and via82cxxx_tune_drive() (hwif->tuneproc will be
NULL for disabled port).

Therefore remove via_enabled variable and now unnecessary
init_dma_via82cxx().  Also do not set .init_{iops, dma} to NULL in
via82cxxx.h (via82cxxx_chipsets[] is declared static).  Bump driver's
version number to reflect changes.

Acked by Vojtech