pm80xx: configure PHY settings based on subsystem vendor ID

Previuosly, all PMC Sierra 80xx controllers are assumed to be a
motherboard controller, except if the subsystem vendor ID was equal to
PCI_VENDOR_ID_ADAPTEC.  The driver then attempts to load PHY settings
from NVRAM.  While this may be correct behavior for most controllers, it
does not work with Adaptec and ATTO controllers since they do not store
PHY settings in NVRAM and choose to use either custom PHY settings or
chip defaults.  Loading random values from NVRAM may cause the
controllers to malfunction in this edge case.

Signed-off-by: Benjamin Rood <brood@attotech.com>
Reviewed-by: Jack Wang <jinpu.wang@profitbricks.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>