net: thunderx: Set queue count based on number of CPUs

81xx has only 4 CPUs, so it doesn't make sense to initialize
entire Qset i.e 8 queues by default. Made changes to queue
initialization to init queues equal to number of CPUs or
8 queues whichever is lesser. Also this will be applicable to
VMs with VNIC VF attached and having less VCPUs

Signed-off-by: Sunil Goutham <sgoutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>