i40e: Remove limit of 64 max queues per channel

It is safe to remove the upper limit of 64 queues on a channel
VSI. The upper bound is determined by the VSI's num_queue_pairs
and gets validated when the queue mapping info through mqprio
interface is subject to bound checking in the driver.

Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>