ASoC: SOF: topology: simplify code to prevent static analysis warnings

ASoC: SOF: topology: simplify code to prevent static analysis warnings

make KCFLAGS='-fanalyzer' sound/soc/sof/intel/ reports a possible NULL
pointer dereference.

sound/soc/sof/topology.c:1136:21: error: dereference of NULL ‘w’
[CWE-476] [-Werror=analyzer-null-dereference]

 1136 |     strcmp(w->sname, rtd->dai_link->stream_name))

The code is rather confusing and can be simplified to make static
analysis happy. No functionality change.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Daniel Baluta <daniel.baluta@nxp.com>
Reviewed-by: Yaochun Hung <yc.hung@mediatek.com>
Link: https://lore.kernel.org/r/20230731213748.440285-4-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>