[SCSI] qla2xxx: Use port number to compute nvram/vpd parameter offsets.

Read adapter's physical port number from interrupt pin register
and use it instead of pci function number to offset into the
nvram to obtain the port's configuration parameters.

Signed-off-by: Anirban Chakraborty <anirban.chakraborty@qlogic.com>
Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>