i40e/i40evf: Add comment to #endif

Add a comment to the #endif to more easily match it with its #if.

Change-ID: I47eb0a60a17dc6d2f01a930e45006d2dc82e044f
Signed-off-by: Helin Zhang <helin.zhang@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>