i40e: Increase minimum number of allocated VSI

This patch increases minimum number of allocated VSIs, so as to resolve
failure adding VSI for VF when 64-VFs assigned to a PF. The driver
supports up to 128 VFs per device, users can decide to enable up to
64-VFs on a single PF, especially 2 X 40 devices. In that scenario, with
VMDq co-existence, there would be starvation of VSIs - with this patch,
supported features would have enough VSIs for configuration now.

Change-ID: If084f4cd823667af8fe7fdc11489c705b32039d5
Signed-off-by: Akeem Abodunrin <akeem.g.abodunrin@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>