eth: sfc: remove remnants of the out-of-tree napi_weight module param

Remove napi_weight statics which are set to 64 and never modified,
remnants of the out-of-tree napi_weight module param.

Acked-by: Edward Cree <ecree.xilinx@gmail.com>
Link: https://lore.kernel.org/r/20220512205603.1536771-1-kuba@kernel.org


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