[PATCH v2] PCI: Remove redundant macro

[zhangdongdong@eswincomputing.com]

From: Dongdong Zhang <zhangdongdong@eswincomputing.com>

Removed the duplicate macro `PCI_VSEC_HDR` and its related macro
`PCI_VSEC_HDR_LEN_SHIFT` from `pci_regs.h` to avoid redundancy and
inconsistencies. Updated VFIO PCI code to use `PCI_VNDR_HEADER` and
`PCI_VNDR_HEADER_LEN()` for consistent naming and functionality.

These changes aim to streamline header handling while minimizing
impact, given the niche usage of these macros in userspace.

Signed-off-by: Dongdong Zhang <zhangdongdong@eswincomputing.com>
---
 drivers/vfio/pci/vfio_pci_config.c | 5 +++--
 include/uapi/linux/pci_regs.h      | 3 ---
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index ea2745c1ac5e..5572fd99b921 100644
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -1389,11 +1389,12 @@ static int vfio_ext_cap_len(struct vfio_pci_core_device *vdev, u16 ecap, u16 epo
 
 	switch (ecap) {
 	case PCI_EXT_CAP_ID_VNDR:
-		ret = pci_read_config_dword(pdev, epos + PCI_VSEC_HDR, &dword);
+		ret = pci_read_config_dword(pdev, epos + PCI_VNDR_HEADER,
+					    &dword);
 		if (ret)
 			return pcibios_err_to_errno(ret);
 
-		return dword >> PCI_VSEC_HDR_LEN_SHIFT;
+		return PCI_VNDR_HEADER_LEN(dword);
 	case PCI_EXT_CAP_ID_VC:
 	case PCI_EXT_CAP_ID_VC9:
 	case PCI_EXT_CAP_ID_MFVC:
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index 1601c7ed5fab..bcd44c7ca048 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -1001,9 +1001,6 @@
 #define PCI_ACS_CTRL		0x06	/* ACS Control Register */
 #define PCI_ACS_EGRESS_CTL_V	0x08	/* ACS Egress Control Vector */
 
-#define PCI_VSEC_HDR		4	/* extended cap - vendor-specific */
-#define  PCI_VSEC_HDR_LEN_SHIFT	20	/* shift for length field */
-
 /* SATA capability */
 #define PCI_SATA_REGS		4	/* SATA REGs specifier */
 #define  PCI_SATA_REGS_MASK	0xF	/* location - BAR#/inline */
-- 
2.17.1