Use estimated throughputs irrespective of RSSI delta for 6 GHz APs

Use estimated throughputs irrespective of RSSI delta for 6 GHz APs

APs in 6 GHz operating with LPI/VLP rules will have significantly lower
SNR values compared to 2.4/5 GHz band APs. Earlier, the estimated
throughputs were used for comparison only when the delta of SNRs between
both the APs was not greater than 7 and as a result for comparing 6 GHz
APs with 2.4/5 GHz APs, estimated throughputs were not getting used.

The estimated throughput calculations takes SNR value also into
consideration, hence remove RSSI delta check if any of the APs are from
the 6 GHz band. This change is limited to the 6 GHz band only in order
to avoid possible regressions with 2.4/5 GHz APs.

Signed-off-by: Vamsi Krishna <vamsin@codeaurora.org>