Add few checks to validate msg from iavf driver.

Test if we have got enough q_vectors allocated in VSI connected with VF.
Add masks for itr_indx and msix_indx to avoid writing to reserved fieldi
of QINT. Clear q_vector->num_ring_rx/tx, without it we can increment this
value every time we send irq map msg from VF. So after second call this
value will be incorrect.

Decrement num_vectors from msg, because last vector in iavf msg is misc
vector (we don't set map for it).
Signed-off-by: NMichal Swiatkowski <michal.swiatkowski@intel.com>
Signed-off-by: NAnirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>