ASoC: amd: acp: Fix devm_snd_soc_register_card(acp-pdm-mach) failure

ASoC: amd: acp: Fix devm_snd_soc_register_card(acp-pdm-mach) failure

Add condition check to fix devm_snd_soc_register_card(acp-pdm-mach)
deferred probe failure, when pdm DSD entry is not available.

[15.910456] acp_mach acp-pdm-mach: devm_snd_soc_register_card(acp-pdm-mach) failed: -517
[15.910536] platform acp-pdm-mach: deferred probe pending: (reason unknown)

Fixes: 6e60db74b69c2 ("ASoC: amd: acp: Refactor acp machine select")

Signed-off-by: Venkata Prasad Potturu <venkataprasad.potturu@amd.com>
Link: https://patch.msgid.link/20250425060144.1773265-3-venkataprasad.potturu@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>