net: sparx5: move stats initialization and add deinit function

net: sparx5: move stats initialization and add deinit function

The sparx5_stats_init() function starts a worker thread which needs to
be cleaned up. Move the initialization code to probe() and add a
deinit() function for proper teardown.

Also, rename sparx_stats_init() to sparx5_stats_init() to match the
driver naming convention.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Link: https://patch.msgid.link/20260227-sparx5-init-deinit-v2-4-10ba54ccf005@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>