octeontx2-af: Fix CGX Receive counters

Each CGX block supports 4 logical MACs (LMACS). Receive
counters CGX_CMR_RX_STAT0-8 are per LMAC and CGX_CMR_RX_STAT9-12
are per CGX.

Due a bug in previous patch, stale Per CGX counters values observed.

Fixes: 66208910 ("octeontx2-af: Support to retrieve CGX LMAC stats")
Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
Link: https://patch.msgid.link/20250513071554.728922-1-hkelam@marvell.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>