wifi: nl80211: store chandef on the correct link when starting CAC

The original change missed updating the correct link ID due to conflict
resolution from another change when moving from v3 to v4. Fix this now.

Fixes: 0b779823 ("wifi: cfg80211/mac80211: use proper link ID for DFS")
Signed-off-by: Aditya Kumar Singh <aditya.kumar.singh@oss.qualcomm.com>
Signed-off-by: Raj Kumar Bhagat <quic_rajkbhag@quicinc.com>
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>