move hdmi/dp channel allocation to a common function
q6dsp_get_channel_allocation() so that we can reuse this across
q6afe and q6apm drivers.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org
Link: https://lore.kernel.org/r/20230509112202.21471-2-srinivas.kandagatla@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org