ASoC: bcm: bcm63xx-pcm-whistler: Check return value of of_dma_configure()

ASoC: bcm: bcm63xx-pcm-whistler: Check return value of of_dma_configure()

bcm63xx_soc_pcm_new() does not check the return value of
of_dma_configure(), which may fail with -EPROBE_DEFER or
other errors, allowing PCM setup to continue with incomplete
DMA configuration.

Add error checking for of_dma_configure() and return on failure.

Fixes: 88eb404ccc3e ("ASoC: brcm: Add DSL/PON SoC audio driver")
Signed-off-by: Haotian Zhang <vulab@iscas.ac.cn>
Link: https://patch.msgid.link/20251202101642.492-1-vulab@iscas.ac.cn
Signed-off-by: Mark Brown <broonie@kernel.org>