qedf: Use hwfns and affin_hwfn_idx to get MSI-X vector index to use

MSI-X vector index is determined using qed device information and
affinity to use.

Signed-off-by: Chad Dupuis <cdupuis@marvell.com>
Signed-off-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>