i40e: Enable VF to negotiate number of allocated queues

i40e: Enable VF to negotiate number of allocated queues

Currently the PF allocates a default number of queues for each VF and
cannot be changed.  This patch enables the VF to request a different
number of queues allocated to it.  This patch also adds a new virtchnl
op and capability flag to facilitate this negotiation.

After the PF receives a request message, it will set a requested number
of queues for that VF.  Then when the VF resets, its VSI will get a new
number of queues allocated to it.

This is a best effort request and since we only allocate a guaranteed
default number, if the VF tries to ask for more than the guaranteed
number, there may not be enough in HW to accommodate it unless other
queues for other VFs are freed. It should also be noted decreasing the
number queues allocated to a VF to below the default will NOT enable the
allocation of more than 32 VFs per PF and will not free queues guaranteed
to each VF by default.

Signed-off-by: Alan Brady <alan.brady@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>