net: mana: Set default number of queues to 16

net: mana: Set default number of queues to 16

Set the default number of queues per vPort to MANA_DEF_NUM_QUEUES (16),
as 16 queues can achieve optimal throughput for typical workloads. The
actual number of queues may be lower if it exceeds the hardware reported
limit. Users can increase the number of queues up to max_queues via
ethtool if needed.

Signed-off-by: Long Li <longli@microsoft.com>
Link: https://patch.msgid.link/20260323194925.1766385-1-longli@microsoft.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>