A program of two chamber works was an unusual choice for the Cincinnati Symphony Orchestra in this weekend’s concerts in Music Hall. The small number of players performing – 23 in the first half and 13 in the second half – made a stark contrast to the large forces onstage earlier this month for a more typical symphonic program of Wagner and Bruckner. But Friday’s program, led by music director Louis Langrée, offered a chance to see some of the star players of the orchestra in a smaller…