docs: octeontx2: extend documentation for Round Robin scheduling

Add example tc-htb commands for Round robin scheduling
Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/device_drivers/ethernet/marvell/octeontx2.rst

@@ -332,3 +332,11 @@ Setup HTB offload
         # tc class add dev <interface> parent 1: classid 1:1 htb rate 10Gbit prio 1
 
         # tc class add dev <interface> parent 1: classid 1:2 htb rate 10Gbit prio 7
+
+4. Create tc classes with same priorities and different quantum::
+
+        # tc class add dev <interface> parent 1: classid 1:1 htb rate 10Gbit prio 2 quantum 409600
+
+        # tc class add dev <interface> parent 1: classid 1:2 htb rate 10Gbit prio 2 quantum 188416
+
+        # tc class add dev <interface> parent 1: classid 1:3 htb rate 10Gbit prio 2 quantum 32768