ixgbe: Move interrupt related values out of ring and into q_vector

This change moves work_limit, total_packets, and total_bytes into the ring
container struct of the q_vector.  The advantage of this is that it should
reduce the size of memory used in the event of multiple rings being
assigned to a single q_vector.  In addition it should help to reduce the
total workload for calculating itr since now total_packets and total_bytes
will be the total work done of the interrupt instead of for the ring.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>