i40e: increase ARQ size

The ARQ needs to have at least as many entries as VFs, or the VFs will
get errors from the FW when they send messages to the PF. Since we don't
know how many VFs we'll end up with, just set up 128 descriptors.

Change-ID: I04ae3d1c7faf09110eb782214e9c05aeb62a6c59
Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Tested-by: Jim Young <jamesx.m.young@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>