i40evf: create a generic config RSS function

i40evf: create a generic config RSS function

Orabug: 22342532

There are two ways to configure RSS, this patch adjusts those two
functions with the same input parameters, and creates a more
generic function for configuring RSS.

Change-ID: Iace73bdeba4831909979bef221011060ab327f71
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>
(cherry picked from commit 2c86ac3c70794f0ecc3684b0ae0fd75b0cf0c1f6)
Signed-off-by: Brian Maly <brian.maly@oracle.com>