wifi: rtw89: fw: implement supported functions of download firmware for WiFi 7 chips

To work with generalized flow of download firmware, implement WiFi 7
specific functions to support it. These functions include disable/enable
WiFi CPU, status of path ready, and status of firmware.

Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230901073956.54203-4-pkshih@realtek.com