Find the clock divisors inside the Plataform Driver, not in the Machine Driver.
Moved the channels/output enable, sample rate setting and sample format to *_hw_params, as discussed on #alsa-soc in freenode.
Implemented sunxi_i2s_set_fmt, get_clock_divder, sunxi_i2s_set_sysclk and sunxi_i2s_set_clkdiv.