wifi: rtw89: mcc: use anchor pattern when bcn offset less than min of tob

When the beacon offset is less than minimum of auxiliary tob
(aux->duration - aux->limit.max_toa), the upper bound of the reference
toa might be negative and lower than the lower bound, which causes the
auxiliary result to exceed the NoA limit. Therefore, in this case, the
anchor pattern is used for calculation.

Signed-off-by: Chih-Kang Chang <gary.chang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20250610130034.14692-11-pkshih@realtek.com