rtw88: remove unused parameter vif in rtw_lps_pg_info_get()

vif is not used, remove it

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