Push some sampling checks to the per-ASIC operations, as they are no
longer relevant for all ASICs.

The sampling rate validation against the MPSC maximum rate is only
relevant for Spectrum-1, as Spectrum-2 and later ASICs no longer use
MPSC register for sampling.

The ingress / egress validation is pushed down to the per-ASIC
operations since subsequent patches are going to remove it for
Spectrum-2 and later ASICs.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>