bnxt_en: Add board.serial_number field to info_get cb

Add board.serial_number field info to info_get cb via devlink,
if driver can fetch the information from the device.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: NVasundhara Volam <vasundhara-v.volam@broadcom.com>
Reviewed-by: NMichael Chan <michael.chan@broadcom.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

@@ -411,6 +411,12 @@ static int bnxt_dl_info_get(struct devlink *dl, struct devlink_info_req *req,
 			return rc;
 	}
 
+	if (strlen(bp->board_serialno)) {
+		rc = devlink_info_board_serial_number_put(req, bp->board_serialno);
+		if (rc)
+			return rc;
+	}
+
 	sprintf(buf, "%X", bp->chip_num);
 	rc = devlink_info_version_fixed_put(req,
 			DEVLINK_INFO_VERSION_GENERIC_ASIC_ID, buf);