i40e: add DCB option to Kconfig

Allow compiling DCB related files if I40E_DCB option
is supported in the kernel configuration.

DCB is disabled by default.

Signed-off-by: Neerav Parikh <Neerav.Parikh@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Tested-By: Jack Morgan<jack.morgan@intel.com>
Signed-off-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/intel/Kconfig b/drivers/net/ethernet/intel/Kconfig
index 333bb54..bb9f0ba 100644
--- a/drivers/net/ethernet/intel/Kconfig
+++ b/drivers/net/ethernet/intel/Kconfig
@@ -271,6 +271,14 @@
 	  Say Y here if you want to use Virtual eXtensible Local Area Network
 	  (VXLAN) in the driver.
 
+config I40E_DCB
+	bool "Data Center Bridging (DCB) Support"
+	default n
+	depends on I40E && DCB
+	---help---
+	  Say Y here if you want to use Data Center Bridging (DCB) in the
+	  driver.
+
 	  If unsure, say N.
 
 config I40EVF