staging: comedi: addi_apci_3120: remove private data 'iobase'

This member of the private data holds the start address of PCI BAR 1 that is
used to access the board registers. The start address is also stored in the
comedi_device 'iobase' member. Use that instead and remove the private data
member.

Remove some unnecessary casts when reading the board registers.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/addi_apci_3120.c

@@ -37,7 +37,6 @@ struct apci3120_dmabuf {
 };
 
 struct apci3120_private {
-	int iobase;
 	unsigned long amcc;
 	unsigned long addon;
 	unsigned int ui_AiActualScan;
@@ -136,7 +135,6 @@ static int apci3120_auto_attach(struct comedi_device *dev,
 	pci_set_master(pcidev);
 
 	dev->iobase = pci_resource_start(pcidev, 1);
-	devpriv->iobase = dev->iobase;
 	devpriv->amcc = pci_resource_start(pcidev, 0);
 	devpriv->addon = pci_resource_start(pcidev, 2);