ASoC: qcom: sm8250: fix HDMI audio playback

Current code does not setup CPU dai (causing -EIO errors on playback)
and does not pass SND_SOC_DAIFMT_I2S to codec fmt (causing i2s-hifi
errors). Fix both errors to enable HDMI audio playback on SM8250. Tested
on RB5 platform.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Fixes: aa2e2785 ("ASoC: qcom: sm8250: add sound card qrb5165-rb5 support")
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>