ixgbe: DCB use existing TX and RX queues

ixgbe: DCB use existing TX and RX queues

The number of TX and RX queues allocated depends on the device
type, the current features set, online CPUs, and various
compile flags.

To enable DCB with multiple queues and allow it to coexist with
all the features currently implemented it has to setup a valid
queue count. This is done at init time using the FDIR and RSS
max queue counts and allowing each TC to allocate a queue per
CPU.

DCB will now use available queues up to (8 x TCs) this is somewhat
arbitrary cap but allows DCB to use up to 64 queues. Its easy to
increase this later if that is needed.

This is prep work to enable Flow Director with DCB. After this
DCB can easily coexist with existing features and no longer
needs its own DCB feature ring.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>