net: sparx5: add support for lan969x targets and core clock

In preparation for lan969x, add lan969x targets to
sparx5_target_chiptype and set the core clock frequency for these
throughout. Lan969x only supports a core clock frequency of 328MHz.

Also, set the policer update internal (pol_upd_int) matching the 328 MHz
frequency of the lan969x targets.

Reviewed-by: Steen Hegelund <Steen.Hegelund@microchip.com>
Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Link: https://patch.msgid.link/20241024-sparx5-lan969x-switch-driver-2-v2-1-a0b5fae88a0f@microchip.com


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