Chris Willman Senior Music Writer and Chief Music CriticEarth, Wind & Fire was alternately singing about the 12th of never and the 21st night of September, but it was all about the 19th evening of June as the veteran group proved an obvious audience favorite during “Juneteenth: A Global Celebration for Freedom,” a multi-artist, multi-genre show at the Hollywood Bowl broadcast live on CNN Sunday to commemorate the national holiday.Held to celebrate the anniversary of Black emancipation in the U.S., the concert spanned almost as wide an array of musical and performance styles as could be packed into a single prime-time slot, from soul to classical to country to jazz. That breadth established, the lineup had a special emphasis on artists that ruled the R&B world of the ’70s, ’80s and ’90s, leading an emcee to joke to the sold-out audience about a time “before all those knee replacements out there.” Even with EWF, Chaka Khan and others getting the crowd on its feet, there may have been no greater eruption of joy during the three hours than the one that occurred during a short set by Bell Biv DeVoe.