net: ethernet: ti: am65-cpsw: Use tstats instead of open coded version

net: ethernet: ti: am65-cpsw: Use tstats instead of open coded version

Make use of struct pcpu_sw_netstats and related helpers to handle
existing per-cpu stats for this driver - the exact same counters
are maintained.

A side effect of this change is to address __percpu warnings
flagged by Sparse:

.../am65-cpsw-nuss.c:2658:55: warning: incorrect type in initializer (different address spaces)
.../am65-cpsw-nuss.c:2658:55:    expected struct am65_cpsw_ndev_stats [noderef] __percpu *stats
.../am65-cpsw-nuss.c:2658:55:    got void *data
.../am65-cpsw-nuss.c:2781:15: warning: incorrect type in argument 3 (different address spaces)
.../am65-cpsw-nuss.c:2781:15:    expected void *data
.../am65-cpsw-nuss.c:2781:15:    got struct am65_cpsw_ndev_stats [noderef] __percpu *stats

Compile tested only.
No functional change intended.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/all/20240911170643.7ecb1bbb@kernel.org/
Signed-off-by: Simon Horman <horms@kernel.org>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>