scsi: megaraid_sas: Fix the search of first memory bar

The 2nd parameter of 'find_first_bit' is the number of bits to search.
In this case, we are passing 'sizeof(unsigned long)' which is likely to
be 4.

It is likely that the number of bits in a long was expected here, so use
BITS_PER_LONG instead.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/megaraid/megaraid_sas_base.c

@@ -5036,7 +5036,7 @@ static int megasas_init_fw(struct megasas_instance *instance)
 
 	/* Find first memory bar */
 	bar_list = pci_select_bars(instance->pdev, IORESOURCE_MEM);
-	instance->bar = find_first_bit(&bar_list, sizeof(unsigned long));
+	instance->bar = find_first_bit(&bar_list, BITS_PER_LONG);
 	if (pci_request_selected_regions(instance->pdev, instance->bar,
 					 "megasas: LSI")) {
 		dev_printk(KERN_DEBUG, &instance->pdev->dev, "IO memory region busy!\n");