wifi: rtw89: 8922a: add chip_ops to get thermal value

Get thermal value as a clue to do RF calibration if the delta is larger
than a threshold, but 8922A doesn't need this, so we only read out the
value when debugging to reduce IO.

Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240124033802.12508-1-pkshih@realtek.com