qcacld-3.0: Fix policy_mgr_is_6G_chan_valid_for_ll_sap() api
Remove only 6 GHz using policy_mgr_is_6G_chan_valid_for_ll_sap()
if WLAN_FEATURE_LL_LT_SAP_6G_SUPPORT is not defined.
Change-Id: I828c61adf3c88c2a5100fff603a007d8a6c85a88
CRs-Fixed: 3532992