ath11k: copy cap info of 6G band under WMI_HOST_WLAN_5G_CAP for WCN6855

WCN6855 has 2 phys, one is 2G, another is 5G/6G, so it should copy the
cap info of 6G band under the check of WMI_HOST_WLAN_5G_CAP as well as
for the 5G band. Some chips like QCN9074 only have 6G, not have 2G and
5G, and this 6G capability is also under WMI_HOST_WLAN_5G_CAP, so this
change will not disturb it.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-01720.1-QCAHSPSWPL_V1_V2_SILICONZ_LITE-1

Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210804181217.88751-4-jouni@codeaurora.org