net: mana: Add gdma stats to ethtool output for mana

Extended performance counter stats in 'ethtool -S <interface>'
for MANA VF to include GDMA tx LSO packets and bytes count.

Tested-on: Ubuntu22
Testcases:
1. LISA testcase:
PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-Synthetic
2. LISA testcase:
PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-SRIOV
3. Validated the GDMA stat packets and byte counters
Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>