ionic: carry idev in ionic_cq struct

Remove the idev field from ionic_queue, which saves us a
bit of space, and add it into ionic_cq where there's room
within some cacheline padding.  Use this pointer rather
than doing a multi level reference from lif->ionic.

Suggested-by: Neel Patel <npatel2@amd.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>