ASoC: qcom: q6apm-lpass-dai: move graph start to trigger

ASoC: qcom: q6apm-lpass-dai: move graph start to trigger

Start the graph at trigger callback. Staring the graph at prepare does
not make sense as there is no data transfer at this point.
Moving this to trigger will also help cope situation where pipewire
is not happy if display port is not connected during start.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
Link: https://patch.msgid.link/20260402081118.348071-12-srinivas.kandagatla@oss.qualcomm.com
Signed-off-by: Mark Brown <broonie@kernel.org>