wifi: rtw89: 8922a: rfk: enlarge TSSI timeout time to 20ms

Firmware needs more time to execute TSSI calibration command. Enlarge
timeout time accordingly, otherwise driver throws messages:

   rtw89_8922ae 0000:03:00.0: failed to wait RF TSSI

Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20240913071340.41822-2-pkshih@realtek.com