ASoC: sti-uniperf: Use default pcm_config instead

The sti-uniperf pcm_config is the same as the default pcm_config.

Since commit 43556516

 ("ASoC: soc-generic-dmaengine-pcm:
Use default config when none is given"), passing a NULL pointer
could let this driver use the default config.

Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
Link: https://lore.kernel.org/r/20231106-sti-uniperf-v1-1-b2d8749cfa2e@gmail.com


Signed-off-by: Mark Brown <broonie@kernel.org>