wifi: rtw89: move H2C of del_pkt_offload before polling FW status ready

The H2C of del_pkt_offload must be called before polling FW status
ready, otherwise the following downloading normal FW will fail.

Fixes: 5c12bb66 ("wifi: rtw89: refine packet offload flow")
Signed-off-by: Chin-Yen Lee <timlee@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230214114314.5268-1-pkshih@realtek.com