bnxt: Read VPD with pci_vpd_alloc()

Use pci_vpd_alloc() to dynamically allocate a properly sized buffer and
read the full VPD data into it.

This simplifies the code, and we no longer have to make assumptions about
VPD size.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -12977,22 +12977,17 @@ static int bnxt_init_mac_addr(struct bnxt *bp)
 	return rc;
 }
 
-#define BNXT_VPD_LEN	512
 static void bnxt_vpd_read_info(struct bnxt *bp)
 {
 	struct pci_dev *pdev = bp->pdev;
 	int i, len, pos, ro_size, size;
-	ssize_t vpd_size;
+	unsigned int vpd_size;
 	u8 *vpd_data;
 
-	vpd_data = kmalloc(BNXT_VPD_LEN, GFP_KERNEL);
-	if (!vpd_data)
+	vpd_data = pci_vpd_alloc(pdev, &vpd_size);
+	if (IS_ERR(vpd_data)) {
+		pci_warn(pdev, "Unable to read VPD\n");
 		return;
-
-	vpd_size = pci_read_vpd(pdev, 0, BNXT_VPD_LEN, vpd_data);
-	if (vpd_size <= 0) {
-		netdev_err(bp->dev, "Unable to read VPD\n");
-		goto exit;
 	}
 
 	i = pci_vpd_find_tag(vpd_data, vpd_size, PCI_VPD_LRDT_RO_DATA);