ath11k: Fix incorrect tlvs in scan start command

Currently 6G specific tlvs have duplicate entries which is causing
scan failures. Fix this by removing the duplicate entries of the same
tlv. This also fixes out-of-bound memory writes caused due to
adding tlvs when num_hint_bssid and num_hint_s_ssid are ZEROs.

Tested-on: QCN9074 hw1.0 PCI WLAN.HK.2.4.0.1-01386-QCAHKSWPL_SILICONZ-1

Fixes: 74601ecf ("ath11k: Add support for 6g scan hint")
Reported-by: Carl Huang <cjhuang@codeaurora.org>
Signed-off-by: Pradeep Kumar Chitrapu <pradeepc@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1607609124-17250-7-git-send-email-kvalo@codeaurora.org