scsi: bfa: Remove useless DMA-32 fallback configuration

As stated in [1], dma_set_mask() with a 64-bit mask never fails if
dev->dma_mask is non-NULL. So, if it fails, the 32-bit case will also fail
for the same reason.

Simplify code and remove some dead code accordingly.

[1]: https://lore.kernel.org/linux-kernel/[e-mail]/#t

Link: https://lore.kernel.org/r/5663cef9b5[e-mail]
Signed-off-by: Christophe JAILLET <[e-mail]>
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/bfa/bfad.c

···
 	pci_set_master(pdev);
 
 	rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
-	if (rc)
-		rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
-
 	if (rc) {
 		rc = -ENODEV;
 		printk(KERN_ERR "dma_set_mask_and_coherent fail %p\n", pdev);
···
 	pci_set_master(pdev);
 
 	rc = dma_set_mask_and_coherent(&bfad->pcidev->dev, DMA_BIT_MASK(64));
-	if (rc)
-		rc = dma_set_mask_and_coherent(&bfad->pcidev->dev,
-					       DMA_BIT_MASK(32));
 	if (rc)
 		goto out_disable_device;