Fix the coefficients of (0:3, 17) in 22.2 to 9.1.6ch down-mix matrix

[sunghee-hwang]

In the proposal related to the down-mix matrix (240617_Expanded_Channel_Layout_Updated.pdf), the coefficients of (0, 17), (1, 17), and (2, 17) are 0.707, 0, and 0.707, respectively. But in the spec, they are incorrectly implemented into 0, 1, and 0.