ath11k: fix survey dump collection in 6 GHz

When ath11k receives survey request, choose the 6 GHz band when enabled.
Without this, survey request does not include any 6 GHz band results,
thereby causing auto channel selection to fail.

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

Signed-off-by: Pradeep Kumar Chitrapu <pradeepc@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210722102054.43419-3-jouni@codeaurora.org