wifi: libertas: use convenient lists to manage SDIO packets

Use convenient lists to manage SDIO packets, adjust
'struct if_sdio_packet', 'struct if_sdio_card' and
related code accordingly.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230725060531.72968-2-dmantipov@yandex.ru