net: dsa: sja1105: make read-only const arrays static

Don't populate read-only const arrays on the stack, instead make them
static.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20230919093606.24446-1-colin.i.king@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>