ice: Add support for VF rate limiting

Implement ndo_set_vf_rate to support setting of min_tx_rate and
max_tx_rate; set the appropriate bandwidth in the scheduler for the
node representing the specified VF VSI.

Co-developed-by: Tarun Singh <tarun.k.singh@intel.com>
Signed-off-by: Tarun Singh <tarun.k.singh@intel.com>
Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>