rtw88: do not use (void *) as argument

The type change from (void *) to (struct rtw_dev *) is redundant.
Just pass the right type and compiler can check that for us.

Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>