For mlo 5+6, 6 GHz band score is higher than 5 GHz, so 6+5 total score is
higher than 5+6, 6+5 is always selected before 5+6 even 6 GHz link score is
much worse than 5 GHz.
To fix it, calculate each link score for each MLO AP, if assoc link is
best link, add a boost score, then it can be selected first.
Update band weight and score for both SLO and MLO, select average of link
band score as MLO band score.
Change-Id: If0714fa94031d5746d89388917540f0e34086d86
CRs-Fixed: 3483850
da25bf14e9