[SCSI] megaraid_sas: Use correct #define for MSI-X capability

Previously we used PCI_MSI_FLAGS to locate a register in the MSI-X
capability.  This did work because the MSI and MSI-X flags happen
to be at the same offsets, but was confusing.

PCI_MSIX_FLAGS_ENABLE is already defined in include/uapi/linux/pci_regs.h,
so no need to define it again.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NAdam Radford <aradford@gmail.com>

drivers/scsi/megaraid/megaraid_sas.h

@@ -1488,7 +1488,4 @@ struct megasas_mgmt_info {
 	int max_index;
 };
 
-#define msi_control_reg(base) (base + PCI_MSI_FLAGS)
-#define PCI_MSIX_FLAGS_ENABLE (1 << 15)
-
 #endif				/*LSI_MEGARAID_SAS_H */

drivers/scsi/megaraid/megaraid_sas_base.c

@@ -3984,12 +3984,12 @@ static int megasas_probe_one(struct pci_dev *pdev,
 	if (reset_devices) {
 		pos = pci_find_capability(pdev, PCI_CAP_ID_MSIX);
 		if (pos) {
-			pci_read_config_word(pdev, msi_control_reg(pos),
+			pci_read_config_word(pdev, pos + PCI_MSIX_FLAGS,
 					     &control);
 			if (control & PCI_MSIX_FLAGS_ENABLE) {
 				dev_info(&pdev->dev, "resetting MSI-X\n");
 				pci_write_config_word(pdev,
-						      msi_control_reg(pos),
+						      pos + PCI_MSIX_FLAGS,
 						      control &
 						      ~PCI_MSIX_FLAGS_ENABLE);
 			}